Sherlock barged into the bathroom where John had gone a half hour ago to take a bath. He expected John would yell and give him yet another lecture on privacy and personal space, but Sherlock needed information on the effects syphilis could have on someone immediately, and besides, thirty minutes was much too long for anyone to sit in a bath for.

But John wasn't in the bathroom. His towel and robe were hanging on the back of the door, and the clothes he had been wearing were folded neatly on the countertop. The bathtub was full, and when Sherlock stuck his hand in he found it slightly below body temperature, but instead of John sitting in there, which Sherlock had expected, there was a toy sail boat sitting in the water.

"And he thinks I'm childish," Sherlock muttered before leaving the bathroom, slamming the door shut behind him. He returned to the couch, deeply confused, the syphilis case immediately abandoned for the more important "Mystery of the Missing John."

Thirty-three minutes and twenty-eight seconds ago he had seen him go into the bathroom. A moment later the water had started. It had been on for four minutes before John had shut it off and presumably gotten in. This means that at some point in the past twenty-eight minutes John Watson disappeared, naked, from the bathroom.

Which makes no sense whatsoever.

So Sherlock made a list of possible places John was.

1. He was kidnapped, and was taken through the window.

But, no, John would have put up a fight, which Sherlock surely would have heard, and besides, John wouldn't fit through the bathroom window. This ruled out the next solution as well.

John left willingly through the window.

Besides the obvious John not being able to fit, Sherlock had confidence in the fact that if John were to leave via bathroom window, he would at least do it clothed.

John was hiding in the bathroom.

There wasn't anywhere for John to hide in the bathroom. The cabinets wouldn't fit him and Sherlock had checked behind the door and shower curtain. And there would have been no reason for John to hide anyway, not during his bath time.

John had managed to sneak out of the bathroom to somewhere else in the flat.

This was rejected immediately for many reasons, among which are included the squeaky floorboards of the flat, John's familiar walk, and the fact that Sherlock definitely would have noticed a naked John Watson walking around the flat.

So Sherlock was left without any explanations, though he did realize that all of his explanations would have been much more plausible had John been a kitten. Which left Sherlock baffled, which he did not like at all.

A few minutes later after making no headway in his new case, he finally decided to go ask Mrs. Hudson if she had seen John. Just as he was standing up, the bathroom door open, and John walked out, wearing his robe and towel drying his hair.

Sherlock stared.

"I'm going to make some tea, would you like some?" John asked him, abandoning his towel on a chair and heading the kitchen. Sherlock followed him.

"But you weren't in there."

"I wasn't in where?"

"The bathroom."

"Yes I was. I had a bath."

"But I went in there looking for you, and you weren't in there."

"You must have dreamt it. I had a perfectly lovely bath with no interruptions." John handed Sherlock his tea. Sherlock set it on the counter beside him without drinking any.

"Well of course I didn't interrupt you. You can't interrupt something that's not happening. I suppose I did interrupt the boat's bath…"

"Boat?" John asked nonchalantly, sipping his tea.

"Yes, the boat you left in the tub."

John rolled his eyes. "You have quite the imagination, don't you? Why would I have a boat in the tub? I'm not a child."

"Yes, that's precisely what I thought."

"I think you should get some sleep. You've been taking on too many cases lately; you were bound to crack sooner or later." John went to walk past him, but Sherlock grabbed his wrist to stop him.

"I have not cracked." Sherlock growled. He glanced down as felt John's hand tense beneath his, and when he looked back up John wouldn't meet his eye. "Are you nervous?"

"No. I would, however, like you to let go of me." John set his tea on the counter beside Sherlock's, and used his newly freed hand to try and pry Sherlock off him.

"Not until you tell me why that boat was there and you weren't."

John rolled his eyes. "What do you want me to say? That… that I can turn into a boat whenever I'm in water? Would that be a sufficient answer to your insane question?" John laughed. Sherlock dropped his hand.

"But that's impossible." People can't turn into boats. People can't turn into anything.

"Yeah, I was kidding," John smiled at him, but Sherlock shook his head.

"No you weren't. You told me the truth using sarcasm hoping I'd realize my claim was ridiculous, and then you'd be free to continue living your life turning into a boat whenever you please."

"So you admit your claim is ridiculous?" John asked.

"Do you deny I'm right?" Sherlock challenged.

John glared up at Sherlock. Neither spoke for a minute, and then John looked away.

"We don't know why it happens." John turned away and ran a hand through his hair. "And I can't do it whenever I want. It just happens."

"For how long?"

"It first happened when I was six. We were at the lake for summer holidays and I went into the water and…" John took a deep breath. Sherlock took a step toward him and gently laid a hand on his shoulder. John leaned into it. "My parents panicked. Well, of course they did, their son had just turned into a boat. Harry cried as they carried me out of the water. And then I just turned back into a boy." John turned to look at Sherlock, and Sherlock saw his cheeks streaked with tears.

"Why are you crying?" He brushed a tear away, not letting his hand linger too long on John's face.

"I don't really like talking about it. I'm a freak, Sherlock. I'm a freak and I can't go in water with other people because I never know when it will happen and I spent years of my childhood being shuttled from Doctor to Doctor because none of them could figure out what was wrong with me. Because something is very wrong with me and I don't know what and I just… I just wish I was normal."

Sherlock didn't know what to say. He's not good with emotions on a normal day, and it's not like there's a book on what to say when you find out your best friend can turn into a boat. "I'm sorry." Simple, yet completely genuine.

"Only my family knows."

"Thank you."

"I think I'm going to get dressed now." John said, and then left, retrieving his dirty clothing from the bathroom before going upstairs to his room.

When he came down ten minutes later he didn't look as though he had been crying. He didn't say anything, just sat down on the couch and turned on a Doctor Who rerun.

Sherlock sat beside him and watched him. He had so many questions, but John didn't seem to want to talk about it, and he probably wouldn't appreciate Sherlock bringing it up, so Sherlock settled with trying to read his mind, something he hadn't done since the summer he was eight and bored and with nothing else to do.

Halfway through his episode John paused Doctor Who and turned to look at Sherlock.

"Fine." He said. "You win. Ask away."

Sherlock wasted no time in getting started.

"I've seen you in rain." It wasn't technically a question, but John would know what he meant.

"It's only when I'm physically in like a body of water. You know, baths, lakes, oceans. It's never happened in rain, nor in the shower, thank God."

"And you can't control it?"

"Nope."

"But it doesn't happen every time?"

"Nope. And before you ask, no, there's no pattern to when it happens. That's one of the things the doctors were testing for."

"Do you always turn into a child's sailboat?"

"When I was a child, yes. But as I got older the type of boat started to depend on the size of the body of water I was in. Also, I think there might be some difference in salt and fresh water, but I don't go into them enough to know for sure."

"Have you tried to control the type of boat?"

"No, I've never particularly cared."

"You know, if you could learn to turn into a cruise ship at will, we could make enough for you to stop nagging me about how we need more money."

John laughed. "I'll think about it. Anything else?"

Sherlock ran through the questions in his head, searching for the most important ones. "Is this why you decided to become a doctor?"

"I suppose. As a doctor I could help others and try to find a cure for myself along the way. And if anyone else came along with a problem like mine, they'd be able to know that they're not alone in this."

"Like you are." Sherlock didn't mean for John to hear him, but he did.

"Like I am," he muttered softly. Sadly.

"No."

"Hm?"

"You're not alone. Well, you are alone in turning into a boat. But you're not alone in life. And you won't be, I guarantee it."

"I don't know if you can guarantee that. You get bored."

"How could I possibly get bored of my best friend army doctor with the psychosomatic limp who accompanies on my cases with little complaint who can do the impossible and turn into a boat?"

"Well when you put it like that…" John smiled at Sherlock, and Sherlock smiled back.

"Besides," Sherlock said, lifting his feet onto the couch and tucking them under John's legs, "I can always help you learn to control it. Because, if you could control it, I have a certain type of boat I'd like you to try."

"Does this certain type of boat have anything to do with your childhood dream of being a pirate?"

Sherlock just grinned.

A/N I don't really know where this came from. I just couldn't sleep the other night and I was lying in bed and thought "John would make a good boat," so then of course I had to write it. Sometimes I just don't understand what goes on in my head.