Summary: This is not about the drug or the girl. This is not about how Martin Crieff lost control over his own body, either. This is a story about how he, Sherlock Holmes woke up from darkness. (AU. Sherlock & Cabin Pressure Crossover in a Jekyll-and-Hyde style. Inspired by the tv show Jekyll in which Hyde was created because of love. )

Disclaimer: Nope, I don't own Sherlock or Cabin Pressure and I don't make a penny out of this.

Hyde and Seek

Since 6 years old, Martin Crieff dreamed about being a pilot though his initial career plan was to become an aeroplane.

Sherlock Holmes knew he was meant to be a consulting detective for…Well…It's a bit hard to estimate the years since he was sharing the mind and body with a useless man who took 7 attempts to pass the pilot qualification. Seriously, it was just a pilot qualification. How difficult was that?

During daytime (depending on which country's time zone you are looking at) he's the Captain Crieff, and at night (Again, time zone is a tricky thing.), he's the delivery boy. Somehow Martin thought that there was some similarity between him and the batman.

Surprisingly, although Sherlock didn't have the main control over the appearance and the body, his "roommate" had absolutely no idea of his existence. When Martin was "driving", Sherlock could observe from Martin's point of view, hear Martin's every little thought and perceive everything Martin had ever laid fingers on. Sherlock envied Martin for freedom. He could only get his playtime when Martin was extremely exhausted.

This was a simple job for Martin. All he had to do was delivering the big box to Ms Molly Hooper at St. Bart's. He should be able to come back in time for the next flight to Chicago.

Sherlock was actually glad that Martin was a pilot. This provided adventures in different countries and saved him finding the excuses not to call Mycroft. Just because Martin and Mark were related in blood, it doesn't mean that their alternative personalities need to be close, not to mention the fact that Martin didn't even know he had a brother called Mark.

He, Martin Crieff, gingery hair, Captain of MJN, was driving a van to St Bart's to deliver a package while he was humming the old song Jekyll Jekyll Hyde. He always found the story a bit absurd. How come a person had distinct personalities and completely different looks? But, man, that was a catchy song.

He, Sherlock Holmes, dark hair, the world's only consulting detective, was sleeping during the journey, and waiting for his moment. When he had the chance, he was going to take some drugs. Research and experiments showed that this could extend his shift a bit longer. He just needed to be patient.

Martin parked the van and went to the reception. The receptionist told him that if he didn't mind, he could carry the heavy box to the morgue since Ms Molly Hooper was currently in the middle of something. It was still early so Martin took the lift and went down.

Sherlock was still sleeping, unconscious and lost in the darkness.

Martin knocked on the door and nobody answered.

"Hello?" Martin opened the door slightly, "I've got your package, Ms Molly Hooper." Curious about the lab, Martin sneaked in.

That is when he saw her through the window.

With a ponytail on one side and pink blouse inside the lab coat, she was concentrating on her work. When she lifted her head, Martin saw her face clearly. She had the cute nose and her lips reminded Martin of cherries.

She was the most adorable girl Martin had ever seen.

His heart skipped a second.

Sherlock suddenly woke up. His version was brighter than usual and he somehow felt warmer. The darkness surrounded him before now began to fade. He could smell the scent of disinfectant fluid.

The girl seemed to notice that someone was staring at her. She stopped working on… Is that a CORPSE? Martin blinked twice. The girl waved at him mouthing "I'm coming." and went to the doors.

Am I…in love?

Then Martin blacked out and dropped the box.

Sherlock opened his eyes and picked up the box.

First time to come out while Martin was still awake. Wired.

"Sorry for keeping you waiting…" The girl entered the lab, "hmm….Hi."

She gazed at Sherlock for a few seconds, "Sorry I thought I saw someone else."

Sherlock lowered his head and looked at his hands which were bigger than Martin's and the trousers felt a bit shorter. Sherlock chuckled and looked at the girl in the eyes, "Yes, he left. This is your package, I believe."

"Thank you. I'm Molly Hooper and you are?"

"Sherlock Holmes."