A/N: I do not own Super Mario or Harley Quinn.

In hindsight, I realized the instructions I'd given Professor Gadd about where to meet me were maybe a bit too vague.

On one hand, I didn't want to pin down a specific location for our rendezvous, out of concern that, even if he technically came alone, a bunch of reporters or paparazzi would independently decide to stake the place out to snap a picture or two of King Boo. And the last thing I needed was for one of them to see Gadd meeting with me, reveal that it was actually me who spray-painted the statue of Peach, and get me arrested for vandalism. I had more important shit to be dealing with, namely rescuing Luigi.

What I hadn't taken into account was exactly how large an area "the woods of Toad Town Park" constituted. And given that the woods could technically be accessed from any side (as long as you weren't opposed to climbing over a dilapidated split-rail fence in some instances), I had to monitor basically the entire forest for Gadd to make sure I didn't miss him.

I really oughta start thinking out my plans more.

So, thanks to the large area I had to patrol, it was about quarter past midnight by the time I finally heard a faint, quavering voice calling, "King Boo? K-King Boo? Y-y-you let Luigi go!"

Well, he sounds pretty much like I expected him too. Same squeaky, paranoid-sounding voice as every other Toad in the Mushroom Kingdom.

As I silently made my way towards his voice, I pondered what Gadd's first initial stood for. Throughout the previous day, the message "King Boo" left for Gadd had been all the news wanted to talk about, which quickly made me aware that Gadd's first initial was "E." Professor E. Gadd. That was all anyone called him. Not "Professor Gadd" or "the Professor" or "Gadd," it was always "Professor E. Gadd." Hell, I don't think I'd even heard anyone once use pronouns when referring to him. It was like all the news anchors were promised extra money for every time they managed to say "Professor E. Gadd" on the air.

As for his first name, my money was on Ernestoad. All Toads might as well be legally obligated to have the word "Toad" pop up somewhere in their first and/or last name. Seeing as how "Toad" wasn't part of Gadd's last name, that meant it had to be part of his first name, which also had to start with "E." Ergo, Ernestoad.

I dropped the night-vision goggles I'd bought that evening over my eyes and continued tracing Gadd's voice. In case you're wondering how I managed to buy a few days' worth of food, the can of King Boo Purple spray paint, and a pair of night-vision goggles with only the money I had on me when I was transported to this universe…I didn't. I actually spent the last of my Earth-616 money on lunch the day I bought the spray paint, but fortunately that wasn't the only source of money at my disposal. I quickly discovered that the Mushroom Kingdom was littered with these giant, golden coins – seriously, you can't go ten feet without finding one of them – that are also recognized as valid currency in these parts. I guess, if nothing else, leaving a shitload of money lying around your kingdom is one way to eliminate poverty.

"King Boo, where are you?" Gadd asked. "How did you get out of the Poltergust? Y-you leave Luigi alone. You've got a problem with me, take it up with me. L-l-leave him out of it."

God, this was depressing. If the real King Boo were here, he could probably sneak up behind this guy, say "Boo," and kill him with a heart attack.

Gadd's voice was getting louder, so I slipped behind a tree and peeked around its side. A second later, Gadd appeared around the side of another tree several years away.

What the shit?

He wasn't a Toad, he was a human. A human with a very Toad-like voice and stature, but a human nonetheless. He wore giant glasses, a lab coat, pointy shoes, and had a solitary spike of hair sticking straight up from his head.

Yeah, about what I imagined when I learned this guy was a mad scientist.

Gadd tiptoed closer. "Sh-show yourself, you evil ghost."

Your wish is my command.

I stepped from behind the tree, hands up, and said, "I come in peace."

"AAAAAAAAH!" Gadd screamed as though he were being murdered (I stand by my previous statement about a "boo"-induced heart attack). He proceeded to try to run backwards away from me, then trip over himself and fall on his ass. "Who are you? Wh-wh-where's King Boo?"

I raised my goggles; I was close enough that I could still see Gadd without the night vision. His hair and coat were white, as I'd expected, and for crying out loud, his glasses were almost as opaque as the ones that turtle-wizard-guy who was working with Bowser Jr. wore.

"Like I said, I come in peace," I said, approaching Gadd like he was a frightened wild animal. "King Boo isn't here. I wrote that message on the statue. My name's Harley. Sorry I scared you, but I need your help and that was the only way I could think of to get your attention."

Gadd crawled backwards away from me, until he found himself backed up against a tree trunk. "H-h-help?" he whimpered. "What do you need my h-help with?"

"Listen, King Boo didn't write that message, but I do think he might've kidnapped Luigi. He's been missing his plumbing appointments lately, and a few days ago I stopped by his house. It looked like there had been a fight there, and I found a smear of ectoplasm on the wall. And, you know, ectoplasm comes from…." Booze. "…Boos."

"And why did you…stop by his house?" Gadd asked suspiciously.

I'm glad you asked. I stopped by his house because I stole a spaceship that belonged to a since-deceased bounty hunter from another universe who Bowser hired to kill Mario, and I discovered that he was planning to kill Luigi too, so I stopped by his place to make sure he was okay. "I heard a bunch of people around Toad Town complaining that Luigi was missing plumbing appointments and, knowing the admirable work ethic he's renowned for, I figured something had to be up."

Gadd rubbed his chin. "Well, ectoplasm certainly means Boos...but King Boo can't have been behind this. It could have been Bowser, after all. It must have been. King Boo's safely stowed away in the Poltergust back at my house."

I raised an eyebrow. "Are you sure?"

"Positive."

"Have you checked the Poltergust since Luigi disappeared? In the past, say, 96 hours?"

Gadd wrung his hands. "Well, n-no, but...but there's no way King Boo could've gotten out. I have motion sensors all over my property, and the booby traps hooked up to them would make Kevin McAllistoad wet his pants! There is no way King Boo escaped from the Poltergust and then made it off my property without me knowing about it."

"Could he have snuck out at the same time that you left your house to, I don't know, get groceries or something?"

"No. The motion sensors recognize the biological signatures of anyone who passes them, so the only way King Boo could've hitchhiked out with me is if he were possessing me. And I know for a fact I would've remembered that happening. But even then, there's no way to open the Poltergust from inside."

"Okay, so someone opened it from the outside." Was he seriously this dense? Come on, these weren't even big leaps in logic I was making here. "Your cat. The UPS guy. A stray gust of wind, for crying out loud."

"I don't have pets for that reason; the Poltergust is in my lab, which has no windows; and I never let visitors into my home for fear that they'll accidentally let captured ghosts loose." He stumbled to his feet. "Well...no, no, she wouldn't."

Okay, now we were getting somewhere. "Who wouldn't?"

"Oh no, it's nothing."

"It sounded like something."

"Oh no, I assure you, it's nothing."

"Okay." I smiled, knelt in front of Gadd, then removed the Fun Gun from my back, where I'd strapped it so Gadd wouldn't see it as I approached him. Gadd gasped, but I shushed him. "This here is my Fun Gun. It's not lethal, but I assure you, it can still shoot a beanbag at your face hard enough to knock out that one tooth left in your mouth. So let's try this again now. Who? Wouldn't?"

"Alright, fine," Gadd said. "I was talking about my girlfriend Helen."

This guy has a girlfriend?

He continued, "I invited her over to my house for the first time last week. She stayed for dinner and then left…but she would never have freed King Boo!"

"Your girlfriend?" I asked, placing the Fun Gun back in its customized holster. "Helen?" That seemed like a strangely…ordinary name to come across anywhere in the Mushroom Kingdom. I wonder what Gadd's first name is, since he's not a Toad.

"Yeah," Gadd said with a dreamy sigh. "Hellen with two l's. Such a lovely spelling, don't you think?"

Wait, two l's? Okay, now the red flags were going off. Because given the ridiculously on-the-nose conventions that names in this place seemed all but required to operate by, I had no doubt that "Hellen" was a pun on "hell." Which, in turn, all but guaranteed she was secretly some evil chick who was only taking an interest in Gadd in order to find King Boo and free him. And then King Boo must've snuck out of Gadd's place by possessing Hellen.

All the pieces were falling into place so nicely.

"And where does…Hellen…live?" I asked.

"Why do you want to know? So you can go hurt her or something? She's nice, I swear!"

Don't tell me this is what I sounded like back when I was with the Joker.

Okay, I clearly wasn't going to be making any progress on that front, so time to try it from another angle. "Well…maybe she accidentally set King Boo free." Yeah right. "And then he possessed her and escaped. See? Maybe she didn't set him free on purpose. Maybe it was an accident after all. And in that case, I'm gonna go stop King Boo and rescue Luigi and Hellen. How about that?"

"Oh," Gadd said. "Well, that's actually quite nice of you." For someone as paranoid as him, he sure swallowed that load of crap pretty willingly. "Well, if King Boo possessed her, they could be anywhere. But for the past several months, Hellen's been living in this abandoned hotel she bought in the Rock-Candy Mountains, called The Last Resort. She's been fixing it up, and she wants to show it to me once it's all finished. She says it'll be so nice I'll never leave."

I'm sure it will. This Hellen woman was reminding me more and more of myself, in another lifetime. Takes one to know one, I guess.

"Well, if you could just give me directions to this Last Resort place, I'll set out for it today and see if I can't exorcise King Boo once and for all."

"Hold up," Gadd said. "I'll come with you. If King Boo really is possessing Hellen, I want to help you save her."

Great. That was gonna make taking out Hellen a hell of a lot harder (pun very much intended).

"No, that's not necessary," I said. "This is a dangerous mission, and you're a...fragile old man. I don't want anything bad happening to you on my watch."

Gadd frowned and might've narrowed his eyes, but I had no way of telling given the opacity of his glasses. "So that's it, huh? Just because I'm old, I'm less competent?"

Great; I'd walked face-first into this one.

He continued, "How about, instead of thinking of me as old, you think of me as experienced? I've been tangling with ghosts for over four decades, which I'd wager is longer than you've even been alive. If you're going up against ghosts, I'm the guy you want on your side."

I gritted my teeth. Well, at least I only need him to get me as far as The Last Resort. Then I can chloroform him or something so I can take care of business without him getting in my way.

"Fair enough," I said. "So how are we gonna get to the resort? Do you have a car-" And if so, do you have a license to drive it? "-or some futuristic airship-thing you've been tinkering on for years?"

"Oh no, I have a car," Gadd said. "Tell you what. I'll meet you out in front of the town hall at high noon. According to what Hellen's told me about where The Last Resort is, we should be able to reach it by nightfall."

"Great. I'll see you then." I started to leave, then turned back. "Oh, and what's up with your voice? I thought you were a Toad."

Gadd adjusted his glasses. "I'm one-eighth Toad. My maternal grandmother's father."

I raised an eyebrow. "One-eighth?"

"Toads have very dominant genes for both height and voice pitch. I predict that it will take no fewer than 287 generations for my progeny to have voices outside the soprano range."

Don't bother asking how he knows that. The answer's probably something stupid.

I gave a curt nod. "See you later."