Dana and Marcus stood in front of a vending machine at the Surprise Hut, inserting coins, pressing selection buttons, and eagerly anticipating candy. The vending machine attempted to drop a bag of candy, but it got stuck.

"No! It's trapped!" Dana exclaimed.

"Everything is terrible forever!" Marcus complained.

Salls walked over to the twins. "You wanna know a trick?" She hit the vending machine with her hands and an elbow, and it opened. "A genius taught me that once," Salls explained, getting candy from the machine. "This just in: weather stations are calling for a...candy blizzard!" She threw candy on the twins.

"Salls, you are the greatest human ever to live," Dana said.

"Hey, no sweat," Salls said. She put her wallet on a table. "I'd do anything for the Pines family."

"Salls!" Silvia called out from the hut's museum. "I need help polishing the exhibits!"

"Coming Ms. Pines!" Salls said as she walked away.

Dana saw Salls' wallet on the table. "Better makes sure she gets her wallet back," Dana said, grabbing the wallet.

"Wait!" Marcus said. "I've never seen Salls' wallet before. Don't you wanna learn some Salls secrets?"

"I don't know if we should be-" Dana began. But then she took out a membership card. "Whoa! Salls has a membership to Laser Tag? I didn't know they let grown-ups in there."

"And look," Marcus said, pulling out a slice of salami. "Emergency salami! Salls, my respect for you has grown."

Dana found a driver's license. "Sally Alzamirana Ramirez," she read. "Organ donor. Birthday: July 13th. Wait a minute. That's today."

"Holy smokes..." Marcus said.

"That's weird," Dana said. "I wonder why she didn't tell anyone."

"Duh!" Marcus said. "It's probably because she wants someone to throw her a surprise party. I can relate. I've been waiting for a surprise party my whole life."

And so, Dana, Marcus, Gary, and Jennifer went to work on planning an outdoor birthday party.

"Wow, you thought of everything!" Gary said, impressed.

"Gary, I'm a bit of a birthday expect," Marcus said. "I've had twelve awesome birthdays in a row, so I know how to make them perfect."

"What about Dana?" Jennifer asked. "She is your twin sister."

"Sure," Marcus said. He laughed nervously. "She also had birthdays."

"Places everyone!" Dana said. "I hear footsteps!"

The four hid behind a table. Cameron lead Salls on since she was wearing a blindfold. "You promised a giant hummingbird," Salls said. "So I'm expecting to see a giant hummingbird."

Cameron yanked the blindfold off, allowing Salls to see the party.

"Happy birthday, you queen on Earth!" Marcus said. "We got everything you love. Cake-flavored pizza, pizza-flavored cake..." He lead Salls to a tent labeled 'Razzle-Dazzler'. "And one more treat..."

The curtain opened to reveal Toby in a red sequined leotard with a big sparkly blue bow dancing. "Razzle dazzle, friends!" he said. "It's the Razz-dazzler!"

"I... I..." Salls stammered.

"Quick!" Marcus said. "Everyone pose for the birthday smiles memory album!" With everyone ready, Marcus took the picture.

When the photo came out, everyone saw that Salls was frowning. "Salls, what's wrong?" Dana asked.

"It's uh... It's nothing," Salls said. "I, uh... I gotta go fix a pipe or something." And with that, she walked away with her fists clenched, her head down, and her eyes closed.

William and Silvia walked in, noticing Salls leaving. "Hey, did you guys see Salls?" William asked. "What happened to-?" He saw the party. "Oh no. Oh no, no. Okay, you guys didn't know so it's not your fault, but Salls hates her birthday."

"What?" Dana and Marcus asked.

"It's a total mystery," William explained. "I guess she's been like this since she was a kid. Some weird personal biz."

"There's gotta be something we can do!" Marcus said.

"We've tried everything," William said.

"I even petitioned the government to have this day removed from calendars," Silvia said. "It didn't work."

Salls was on the porch looking at an old picture. She sighed sadly. The others watched her from behind the house. "I don't know, guys," William said. "Maybe we should just leave her alone."

"No one should be alone on their birthday," Dana said. "There's gotta be a way to cheer her up. We just have to try harder."

"You're right, Dana!" Marcus said. "It's time for us to bring out the big guns!"

And so, Dana, Marcus, Silvia, William, Cameron, Gary, and Jennifer brought Salls to Big Gunz Laser Tag. "Alright, guys," Salls said, wearing a blindfold. "Blindfold me once, shame on you. Blindfold me twice- Wait a minute. Hot dog smell? Sticky floors? Future sounds?" She took off the blindfold. "Laser tag? I-I love laser tag! How'd you guys know?"

"We definitely didn't rifle through your wallet," Marcus lied.

Some time later, the group got their laser tag gear on. A voice was heard over the speakers.

"Welcome to the year 8000. Society: collapsed. Fog machines: everywhere."

William noticed the walls. "Are these walls just mattresses spray-painted purple?" he asked.

"I think this place used to be a mattress store," Silvia said.

"I-I don't know, guys," Salls told Dana and Marcus. "I'm not sure I'm up to this today."

"Don't worry, Salls," Dana said. "As soon as you start playing with us, you're gonna have a great time."

"No matter what happens, we won't leave your side," Marcus said.

"Well, I guess I could give it a shot," Salls said.

But then, just as the group entered the battle zone, Dana and Marcus disappeared in a flash of light. "Marcus?" Salls asked, looking around. "Dana?"

"Whoa, this is even cooler than I imagined!" Marcus said, looking around the blank room.

"Wait a minute..." Dana said, looking around. "Where is everybody?"

"Hello, Dana and Marcus Pines."

To the twins' surprise, time traveler Brandy Blandin materialized in front of them.

"The time traveler woman!" Marcus exclaimed.

"Brandy Blandin?" Dana asked. "What did you do to us?"

"It's an interesting story," Brandy said. She pressed a button on her wristwatch and a holographic screen was projected. "After you 'borrowed' my time device to make a slight alteration to your timeline without drastically changing history, I was promoted to top officer of the Time Anomaly Removal Crew. While I did fail to track down the Guardian of Time and Space, the great Time Baby gave me a new assignment: when the time comes, I must initiate an important time traveler test for the both of you. I spent every day since then planning the test. And now finally, it has come!"

"Look, we're sorry about the whole 'stealing your measuring tape' thing," Dana said. "But we're in the middle of something really important right now."

"It's our friend's birthday today, and we promised we wouldn't leave her side," Marcus said.

"Do you think some birthday matters right now?" Brandy asked. "People have said that it's an honor to take part in a time traveler test." She pulled out a time device. "All you have to do is accept it."

Dana sighed. "Do we have any other choice?" she asked.

"Nope," Brandy said. "You have to take this test."

"Alright," Dana said, grabbing the time device.

"I just hope Salls is doing alright," Marcus said.

Back at the laser tag arena, Salls walked around. "Dana? Marcus?" she called out. "Requesting backup!"

While that was going on, William was chasing Becca around, firing his laser gun at her chest plate.

Dana pulled out the measuring tape, then she let go of it and linked arms with Marcus. They disappeared in a flash of light.

Dana and Marcus landed on a mattress. "Are we back?" Marcus asked.

Dana looked around. "I don't think so," she said. "The laser place is a mattress store."

"Why would Brandy send us here?" Marcus asked. "She never really explained what the whole point of a time traveler test is."

"We better go back and ask her," Dana said.

Marcus looked at the time device. "I don't think we can," he said, holding up the dented time device. "Can you fix it?"

"Maybe," Dana said. "I need some tools." She saw a sign outside that read 'SURPRISE HUT 1 mile'. "And I think I know where to get some."

Dana and Marcus left the mattress store. "Let's try to lay low," Dana said. "We don't want to change the future. Or cause the future. I forget how this works exactly."

A biker girl was listening to a boom box mounted on her shoulder. Chief Blubs had longer hair, and the dark-skinned security guard was getting his first tattoo. A billboard showed Bonnie and baby Jennifer and read 'FIFTH WHEEL JUST HAD A BABY SALE'.

"Wow, ten years in the past," Marcus said, looking around. "Everything is same-y, but also different-y."

Toby was dancing at a studio. "Look out Broadway, here I come!" he said, looking at a poster.

Marcus banged on the glass to get Toby's attention. "You're going to make it big someday, Toby!" he called out.

"Yes!" Toby cheered, still dancing.

Dana and Marcus continued down the sidewalk. Bonnie was pushing a stroller, which apparently contained her baby daughter. Young versions of Taylor and William rode up to the twins on tricycles. "Oops, sorry," Taylor said.

William stared at Dana, like he was in some kind of trance. "You're cute," he blurted out.

Dana blushed. "Thank you," Dana said. "I mean...you're super young, so this is weird."

"At least we now know he has a thing for brunettes," Marcus said.

Dana suddenly remembered what William told her at the Surprise Fair.

"Ten years ago, Taylor and I were biking when I saw a brown-haired girl. I didn't really get to know her that well, but I thought she was the cutest girl I ever saw."

"Are you sure this girl looked like me?"

"Yeah, I'm sure. Same outfit and everything. Well, except for the metal plate on her chest."

Dana realized she was still wearing her laser tag vest. Did she just close a time loop?

Soon, Dana and Marcus arrived at the Surprise Hut. "Step right up, ladies and gentlemen, to see my latest attraction," Silvia said. "Behold, the great wax museum!"

Dana took off her laser tag vest. "The coast is clear."

Marcus took off his laser tag vest. "Now's our chance!"

The twins got in the hut through the window. Dana found a red screwdriver and picked. "Alright, let's see..."

A girl banged on the vending machine. "Ah, c'mon candy," she said. "Fall. Fall."

Marcus walked over to the vending machine. "Allow me," he said. "You just need to know a guy on the inside." He copied Salls' method of opening the vending machine, allowing him to reach in and grab some candy. "Jackpot!" He turned around to face the girl and he gasped. It was a younger version of Salls!

"Thanks," Salls said, taking the candy from Marcus. "You must be some kind of genius."

Meanwhile, Dana finished fixing the time device. "I think I've got this thing working," she told Marcus.

Marcus shook Dana. "Dana, Dana. Look." He showed her Salls.

"No way," Dana said.

"You keep wandering off," Abuelito told Salls. "You don't want to be late for your big day."

"Sorry, Abuelito," Salls said as Abuelito escorted her out of the hut.

"Big day?" Marcus asked. "This could be the birthday where that personal biz went down. We could finally find out why Salls hates her birthday!"

"Alright," Dana said, looking at the time device. "But let's be quick."

At the Ramirez household, there was a birthday party in the backyard. Dana and Marcus are spied on the party from behind bushes.

"I don't know why Salls hate her birthdays," Dana said. "This looks great."

Salls saw a kid take a seat. "Uh, sorry, but could you move seats?" she asked. "Those two are the seats of honor."

"For who?" the kid asked.

"My parents," Salls answered. "I haven't seen them in three years. But they're coming today!" She heard the doorbell ring. "That must be them!"

Marcus and Dana followed Salls, looking in through a window. Salls opened the door, only to see a mailman. "Picture for a miss Sally Ramirez," he said.

Salls took the picture, which was of a man and a woman, along with a young girl. Salls flipped over the picture and read the message out loud.

We decided to adopt a new daughter. Hopefully she won't turn out to be a freak like you were.

Salls gasped as Reggie approached her. "Hey, don't worry about it, cuz," he said. "Guess they didn't appreciate how special you are."

"I'm gonna go lay down," Salls said. "You party without me." She walked to her room.

"Wait!" Abuelito said. "What about your presents?"

"So that's why Salls hates her birthday," Dana said. "It's the day her parents disowned her."

"How much partying can fix that?" Marcus asked.

"I don't think we can fix it," Dana said. "We promised Salls a happy birthday, but how can we give her that now? This goes beyond anything we know how to fix."

Brandy appeared next to the twins. "There is one way to help your friend," she said. "Use a time wish."

"A time wish?" Marcus asked.

"It's a powerful object that can do literally anything," Brandy explained. "Any impossible problem solved..." She snapped her fingers. "...just like that. Imagine the possibilities."

"Of course!" Dana said. "If we get this so-called time wish..."

"Then we can wish that Salls' parents accepted her and they came to her birthday!" Marcus said.

"And Salls' birthdays would be fixed forever," Dana said. "All of them."

"So how do we get a time wish?" Marcus asked.

"There's only one way to get a time wish," Brandy said. "You must defeat me in a game of Globnar!"

Dana and Marcus were confused. "Oh, right," Brandy said. "Globnar is gladiatorial time combat. The winner gets a timre wish, and then decides the loser's fate."

"Do you really think we can win Globnar?" Marcus said.

"I'm sure," Brandy said. "It's the only way to complete the test. Now, let the Globnar begin!" She pressed a button on her wristwatch, and the group disappeared in a flash of white, leaving a red screwdriver behind.

The group reappeared inside the Globnar arena. When Dana and Marcus were shown on a large screen at the edge of the arena, a lot of people in the audience started complaining.

"Seriously?! These two again?!"

"What a rip-off!"

"I want my money back!"

"Welcome Globnar tributes!" Time Baby said. "You each have a change to settle your time-feud through gladiatorial com-" He saw Dana and Marcus. "Wait a minute..."

"Wait Time Baby!" Brandy said. "This is Dana and Marcus! This Globnar match is part of their time traveler test!"

Time Baby used telekinesis to have a closer look at Dana and Marcus. "Hmmm... The one with the hat does have longer hair," he said. "Very well." He put the twins back on the ground. "But this better not be the same as the previous match!"

And so, the Globnar game began. The three competed in various rounds. They fought with sticks, rode futuristic cycles that can defy gravity, played chess, rode a giant wheel, ate hotdogs, fought in robotic cuckoo clock suits, had a wheelbarrow race, fought with spears on unicycles on a tightrope, played Jenga, and participated in laser tag. It ended with Dana and Marcus winning.

"It is finished!" Time Baby announced once Marcus grabbed the time wish.

However, the audience booed, with Dana and Marcus hearing complaints how it was exactly the same as the previous match.

"You have made victory in Globnar," Time Baby told Dana and Marcus. "Before I give you your time wish, tell us; what fate have you decided for the loser?"

"Nothing really," Marcus answered with a shrug.

"Hold on," Dana said. "We would like her to answer a few questions."

"So be it," Time Baby said.

"Alright Brandy, what's going on?" Dana asked. "Why is everyone saying our Globnar match is exactly like the previous one?"

"And why did everyone mistaken us for someone else?" Marcus asked.

"I guess you deserve to know the truth," Brandy said. She pulled up a holographic image. "Your home universe isn't the only one that exists. There is a vast number of dimensions in existence. Yours is called Dimension 63, and for some strange reason, it is connected to a dimension called Dimension 46'\, although most people simply call it Dimension 46. If there is someone existing in Dimension 63, there is a counterpart in Dimension 46 that may or may not be the opposite gender. And these are your counterparts: Dipper and Mabel Pines." She showed Dana and Marcus a picture of their Dimension 46 counterparts.

"Holy smokes!" Marcus exclaimed. "I look like a girl!"

"Someone told me I had a counterpart who embraced that horrible nickname kids call me," Dana said, recalling her encounter with Bill. "Guess that's what he meant by that."

"Now what about our test?" Marcus asked. "Did we pass?"

"You sure did," Brandy answered. "Your actions in the year 2002 closed a time loop. Observe." She used her wristwatch to show a video of young Salls.

"Whoa," Salls said. "I thought I heard an explosion." She saw the screwdriver Dana dropped. "Whoa, what's this?" She read the print on screwdriver. "Surprise Hut."

Salls got to the Surprise Hut and approached Silvia, who was about to put up Help Wanted flyers. "Excuse me, miss," Salls said.

"Oh, hello there, sweetie," Silvia said, putting the flyers on a table. "Do you know how to fix a golf cart?"

"Well, uh..." Salls stammered. "I don't know if I-"

"It's okay," Silvia said, giving Salls a staff shirt. "I'll help you out as part of your training. From now on, you're officially part of the Surprise Hut crew."

"And that's not all," Brandy continued. "You also improved someone's future." She showed the twins a hologram of a poster that read 'Ghost of the Musical: Now Featuring Tony Award Winning Actor Toby Determined'. "And your reward is a time wish."

"Now, children," Time Baby said. "What is it that you want for your time wish?"

"Thank you, but the wish isn't for us," Marcus said.

"Not you?" Time Baby asked. "But then who? Who is worthy to receive such power?"

At the laser tag arena, Salls left the combat area. She walked up to the exit and flipped a coin, wondering if she should stay or leave. Suddenly, Dana and Marcus appeared with Brandy.

"Salls!" Dana and Marcus exclaimed.

"G-Guys!" Salls said.

"We're so sorry we left you hanging," Dana said. "We got caught up in this time travel junk."

"And there was a time cyclops," Marcus said.

"And don't forget about the time race," Dana said.

"But, the point is, Salls, we think we know how to fix your birthday," Marcus said.

"Whoa, really?" Salls asked. "Wait, you guys did all of that...for me?"

"And that's not all," Brandy said. She pressed a button on wristwatch and the time wish appeared. "Behold your time wish! The power to alter time paradox-free in any way you choose."

"We think the only thing that can make you happy is reuniting with your parents," Dana said.

"But the choice is yours," Marcus said.

"You mean I can finally see my parents by touching this thing?" Salls asked. "And you guys battled through time and space just to get this for me?"

"What are you waiting for, Salls?" Dana asked.

Salls was about to put her hand on the time wish, but then she backed up. "No," she said.

"But Salls, what about your parents?" Dana asked.

"Well, birthdays are supposed to be spent with the people who care about you," Salls explained. "But you know what, my parents didn't care about me at all, let alone fight monsters through time and space like you two. I mean, you had a gladiator fight, just to make me happy. I've been being ridiculous this whole time. Wherever my parents are, they can take a hike. I know who my family is now, and it's you two." She gave the time wish back to Dana and Marcus. "That's why I'm giving the time wish back to you."

"Really?" Marcus asked.

"It's okay," Brandy said. "Think of it as a reward for passing the test."

Looking at each other, Dana and Marcus placed their hands on time wish and it gave off a flash of white light. When it cleared, a #2 pencil with an infinity symbol engraved on it appeared in Dana's hand.

"So what did you two wish for?" Salls asked.

"An infinite pencil," Dana said. She broke the pencil tip, which regenerated. "Now I won't have to sharpen pencils ever again."

"I wished for the ability to become a merman when I dive into large bodies of water," Marcus said. "Now I can visit my mermaid girlfriend whenever I want."

"Those are good time wishes," Brandy commented.

"You know, there's still ten minutes before Laser Tag closes," Salls said. "You wanna play?"

"Yeah," Dana said.

And so, Dana, Marcus, and Salls ran into Laser Tag zone, laughing. Satisfied with her accomplished mission, Brandy went back to her home in the future.