Once David and Mary Margaret arrived back at Camelot, they sought out Regina, telling her they could trust King Arthur. And that they should hand over the Dark One dagger to him. However, Regina didn't know that King Arthur had placed a spell over David and Mary Margaret, making them say what King Arthur wanted them to believe.

As Regina led the two through the woods, she still wasn't sure it was the best thing to do. In the morning, they said they couldn't trust King Arthur. And what had happened to the Doctor? "You think giving the dagger to Arthur is the best way to help Emma?"

"We trust him," Mary Margaret answered.

"Implicitly," David agreed.

Regina turned to look at him. "Did you learn those big words at shepherd school? How do you know you can trust him?"

"Because we're good judges of character," David told Regina. "And we would never act against Emma's best interest."

Mary Margaret saw Regina head over to an old tree stump with moss. She went over to it with her. "Is the dagger in there?"

Regina reached inside and pulled out the Dark One dagger, which was wrapped in an old cloth. She held it out to Mary Margaret but pulled it to herself again. "Are you sure handing the one thing that can control your daughter over to Arthur is the right thing to do?"

"Have you lost the power of comprehension?" Mary Margaret asked, growing impatient by the second. "Hand over the da…." But before she could finish her sentence, she and David were frozen magically by a yellow glow.

Regina looked around, then saw Emma walk towards her. She sighed. "What are you doing? When did you get so liberal with dark magic?" she asked, walking towards the blonde.

"Since me," came the Doctor's voice.

Regina turned and saw the Doctor walk towards them.

"Arthur has the Wonder Twins over there under some spell. He tried to do the same to me. Luckily, Time Lords make lousy slaves," the Doctor said.

Regina tilted her head. "Why would he put them under a spell?"

"He wants to reunite Excalibur with the dagger," Emma answered.

"Unite it?" Regina asked.

"The two blades were once one blade," the Doctor explained.

"And was broken in half a long, long time ago," Emma continued.

"What happens when they're together?" Regina asked.

"Arthur wants to kill Merlin with it. I don't have to tell you how bad that would be for all of us."

"How do you know this? Wait … You two took a trip back in time, didn't you?"

Emma shook her head. "I saw it in a dreamcatcher."

"That's dark magic. Emma, you can't keep using it."

"It's a risk I'm willing to take. Besides, you must wave a dreamcatcher over someone to capture a memory."

"I don't," Emma told her. "This dark magic is stronger and more unpredictable than any magic I've ever used. The image just appeared. It showed me what Arthur did to them. But, look, it's going to be okay. The dreamcatcher also showed me a memory that's going to help us. Merlin's. I saw him. Merlin wept for the loss of the only woman he ever loved moments before the Dark One trapped him in the tree... using one of his tears."

Regina listened to what Emma had said. "Emma. I think that's it. That's the key to freeing Merlin," she began. "Sometimes, spells are like snakebites. You can make the antivenom with the venom. If a tear of lost love trapped Merlin, then another might be able to get him out. So, what do you say? Let's go get ourselves a tear."

While the three walked back to Merlin's tower at Camelot, they saw Henry in the middle of the woods, practising with a sword. However, it wasn't long before he dropped it and scattered to pick it up.

"Henry, be careful," Regina said.

Henry turned around to see both his mothers and the Doctor standing behind him. "Hey, Mums. Hey, Doctor. I was getting in the Camelot spirit. You know, trying to understand this world."

"By sword fighting?" Emma asked.

"Well, Sir Morgan, Violet's father, had some advice for me to fit in. That's all. The trouble is, I'm not sure if I will ever be good at this knight stuff."

"Let me give you advice," the Doctor said. "Better advice than this Sir Morgan. You are an interdimensional traveller. You are mysterious. Use it."

"The Doctor's right," Emma said. "Changing for someone else never works. I mean, I liked your dad because he was always himself."

"But maybe if I try, I could be something better than I am," Henry replied, then looked at Regina. "If you didn't change for the better, you wouldn't be with Robin."

"True," Regina said. "But do you think a girl from Camelot would be interested in someone who's just like every other boy around here? Remember when I told you about Daniel?"

Henry nodded. "Yeah. He was your first love."

Regina nodded. "Right. And it wasn't because he tried to impress me by being like the others. It was because he was so different. So unique. And so … Mysterious." She glanced at the Doctor.

Henry looked over at the three of them. He hadn't thought of it like that before. "I think I can work with all of this. Thanks." He began to turn and head in the opposite direction. "I have to go make a few arrangements."

"Emma," Regina began once Henry was gone. "I think I might know where to get our missing ingredient to free Merlin. From me."

Back at Camelot, Regina sat in a chair in her quarters opposite a roaring fire. Emma approached her, carrying a dreamcatcher in her hands. "Alright, Regina. This is going to be intense. Last chance to back out."

Regina shook her head. She had to do this. She had to be strong, even though she hadn't thought of this moment for so long. "I can take it."

Emma gave Regina the dreamcatcher and sat down in front of her. "Look into the circle," she said, waving her hand over the dreamcatcher, watching as Regina's memories filled it. Memories between Regina and her mother, Cora.

"So, this is your decision?" Cora asked. "This will make you happy?"

"It already has," Regina told her mother.

"Then who am I to stop you?"

Smiling, Regina approached her mother and hugged her. "Thank you, Mother."

Cora's gaze shifted from Regina to Daniel standing behind her. "Daniel…" Cora began, moving over to her. "If you want to have a life together, a family, then there's one important lesson I can impart to you. It's what it means to be a parent. You always have to do what's best for your children." Then, Cora plunged her hand into Daniel's chest, ripping it out of his body. She looked down at the glowing red heart in her hand before squeezing it tightly and watching as it turned to dust, killing Daniel.

Regina watched, horrified at what was happening. She ran over to Daniel's limp body. "Mother! No! No!" she cried.

The memories faded from the dreamcatcher, and Emma watched as Regina began to sob from watching the painful memory. "I'm sorry."

"It was like it was happening all over again," Regina replied.

Emma moved forward and captured one of Regina's tears in a vial. "Got it. Thank you. I didn't know how things were for you. I… didn't know…"

"You could see it, too?" Regina asked.

"I don't understand how a mother could do something like that," Emma replied.

Regina sighed. "She thought it was for the best."

Taking the tear in the vial and other magical potions to the tree in the courtyard, they prepared to free Merlin from his confines in the tree. Emma stared at everything on the far wall. She didn't know if she could do the task before her.

"Go on, Emma," Regina told her. "Do it. Arthur can be here any second."

Emma took a breath and poured potions into a small bowl. She stirred everything together.

Regina took out the vial of her tear and handed it to Emma. "Now for the final ingredient. The tear."

Taking the vial, she poured it into the bowl. The potion poofed upward but then dissipated into the air.

Regina sighed. "It should've worked. It should have worked."

"Regina, it's simple," Emma said. "Your heartbreak wasn't strong enough."

"What?" Regina scoffed.

"But there's Robin now. You've moved in. You've healed."

"Hey. Sorry, I'm late," came a voice behind them.

They looked behind and saw Henry coming up toward them.

"Henry, are you okay?" Emma asked, sensing something in his voice.

"Yeah. I'm … I'm fine."

Regina looked at him. "No, you're not," she said, sensing the same thing that Emma had. "What happened?"

"Henry?"

Henry shook his head. "I don't want to talk about it."

"You can tell us anything," Emma said.

"I tried doing what you said. I tried acting like myself," Henry began, but his voice began to break, and tears started filling his eyes. "But she didn't want anything to do with me."

Emma placed a hand on Henry's shoulders. "Henry."

"Violet's right. In this world, I'll never be a hero."

"You may not be a hero in her world, but you will be in ours," Regina told Henry as she wiped away Henry's tears. "This'll work. This tear. Your tear, Henry."

"It can free Merlin?"

"You can save me, kid," Emma said.

"Stop!" came a voice from behind them. They turned around and saw King Arthur and his knights approach them. "Stay away from the tree. I won't ask twice. You and your people have done nothing but lie to me ever since you got here." King Arthur turned to Regina. "You're no Saviour. You're a fraud!"

Regina turned to face them. "Go ahead," she snarled. "Call me a fraud again. I dare you."

"We welcomed you, celebrated you. And in return, you bring the Dark One into the heart of my kingdom. Endangering all who live here. Give me the dagger!"

"You want it?" Regina asked, and she conjured a fireball in her hand. "Come and get it." She turned to Emma. "Now, Emma."

Emma took the handkerchief from Regina's hand and raced to the other ingredients. She mixed them before adding the tear. The potion swirled and smoked upwards as the white light swirled around Emma, mixing with the Darkness. "It's working," Emma exclaimed.

"Charge!" King Arthur ordered his knights, but Regina threw her fireball at them before conjuring another.

The black and white swirls absorbed Emma, and she used them to aim at the tree. The swirls swirled around the tree until there was nothing but a man in a hood.

The man lowered his hood, and he stared at Emma. It was Merlin. "I've been waiting for you … Emma," he told her. Then he turned to King Arthur. "And you … The boy who would be king. My great hope. How you've disappointed me."

"I disappointed you?" King Arthur spat. "You gave me false prophecies. Sent me on an impossible quest! You ruined my life!" He drew Excalibur and raised it at the great wizard.

Merlin didn't flinch. "Put it away, Arthur. We both know that broken sword can't hurt me."

After a moment, King Arthur sheathed the sword away. "This is not finished," he said before walking away.

The following day, Emma, Regina, Henry, Robin, Belle and the Doctor were at the abandoned cottage, where they stood and watched as Merlin used his magic to clear the minds of Mary Margaret and David – erasing any trace of the Sands of Avalon from them.

"There," Merlin said with a smile. "That should do it."

Mary Margaret looked around, then looked over at her daughter. "Emma," she said, hurrying over to hug her. "We're so sorry."

"If we'd have known how bad Arthur was …" David began.

"It's okay," Emma interrupted. "I'm just glad Merlin could help."

"Merlin?" David asked, his gaze looking at the new person in their group. "You're Merlin?"

"Expecting someone …" Merlin began.

"Older," David finished.

Merlin sighed. "Yes. Let's say that being a tree … Good for your skin."

"Well, now that the great Sorcerer is among us, maybe he'll tell us," Hook said as he approached. "Can you do what the Apprentice said? Can you free Emma from the Darkness?"

"Sure. But with a caveat," Merlin replied. "Darkness like this takes hold of the person and finds its way deep inside where nobody else can see. So if I am to free you from its grasp, I must know one thing. Emma, is your heart truly ready to be free? Because it is as much up to you as me."