This is my first attempt at a Cross Over Fan Fiction but I hope you enjoy it. It's a cross over of 2 of my favourite sitcoms and I really loved writing it so enjoy


The Big Bang Theory created by: Chuck Lorre and Bill Prady

The IT Crowd created by: Graham Linehan


Things were normal in the IT Department at Reynholm Industries, London, England with Roy and Moss working on their computers and waiting for the phone to ring so they could go up and fix peoples computers, after they had tried turning them on and off again and made sure they were plugged in, of course. Jen, on the other hand, as usual wasn't doing much due to her lack of knowledge about computers. She giggled to herself as she remembered how Moss and Roy had told her not to open the red door, which of course she did and had discovered their Goth work colleague Richmond. She also remembered how Roy's warning about not opening the green door.

Meanwhile in Pasadena California, USA, Dr Sheldon Cooper a theoretical Physicist was working on his laptop while his roommate and colleague, Dr Leonard Hofstadter was trying to clean their apartment which Sheldon was finding bot distracting and disturbing.

"Do you have to clean around the apartment now I'm on a breakthrough?" whined Sheldon.

"Well sorry Sheldon we haven't cleaned this place in months the dust on the cabinets is at least an inch thick," replied Leonard. "It's upsetting my asthma."

"Fine just be a little quieter if you don't mind,some people are trying to work here," snapped Sheldon.

"Oh then I'll be very quiet," sighed Leonard.

Leonard pushed aside one of the cabinets with their action figures on it when he realised he'd never remembered either of them ever cleaning behind there before. Behind the cabinet was a small wooden door Sheldon had never mentioned before.

"Sheldon what's behind this door behind the cabinet?" asked Leonard.

Sheldon's head shot up as if Leonard had discovered something he didn't want him to discover.

"Oh that nothing it was here when I moved in its nothing," said Sheldon quickly sounding untruthful.

"Oh really well if we've never used it why don't we use it to store some of our extra stuff?" asked Leonard.

"Because it's locked and I never got a lock smith for it," said Sheldon.

"Well why don't I check." Leonard grabbed the knob, turned it and to his surprise it wasn't locked as Sheldon claimed.

"Wait don't open it," said Sheldon sharply stopping Leonard from opening it, pulling his hand away from the knob.

"Why not?" asked Leonard.

"Because I've never opened that door before and if you do I shall become very difficult to live with," said Sheldon.

"Alright, alright I know what happens when you become difficult to live with. I won't open the door," said Leonard.

"Good and promise me you'll never even look behind this cabinet again," said Sheldon.

"I promise," sighed Leonard.

Meanwhile at Reynholm Industries Jen decided that even through Moss and Roy had told her not to open the green door as the Head of the IT department she felt she had a right to know what lay behind it. So just before lunch she decided to ask again.

"Moss, Roy can I ask you guys a quick question before you guys head off for lunch?" asked Jen.

"Sure go ahead ask away," said Moss giving her his full attention.

"Since I know what's behind the red door, I think you should tell me what's behind the green door?" asked Jen.

"Nothing!" they stated together.

"Oh come on guys, not this again," whined Jen.

"We told you not to open the red for a good reason now listen to us when we say don't open that door, it will destroy the entire rainforest," said Roy.

"I won't open it, I just want to know what's behind it," Jen wheedled.

"We also had good reasons for not telling you what's behind the red door so why should we tell you what's behind the green door?" asked Moss.

"I am the Head of the IT department I have a right to know what's behind the green door," demanded Jen starting to raise her voice.

"Alright, alright we're sorry," Roy tried to calm her, "But to be true we don't actually know what's behind the green door."

"Oh sure or you're just making up another excuse not to tell me what's behind the door," said Jen.

"No we really don't know. As god is our witness we don't know," stated Moss trying to sound definite.

"Wait! If you don't know what's behind the green door why have you never opened it?" asked Jen slowly.

"Because the last guys who worked in IT here told us to never open the green door because of some experiment they did with some crazy scientist from Pasadena," explained Roy.

"So you've never opened that door even out of curiosity?" asked Jen.

"We've learnt not to let our curiosity get the better of us," said Moss.

"So trust us do not open the green door," said Roy sounding out every word.

"Alright, alright I won't open the green door," said Jen defensively.

"Good let's keep it that way," said Roy sounding relieved.

Roy and Moss decided to go to the park for lunch despite Moss being caught for shop lifting last time they went. Jen left with them but couldn't stop wondering what could be behind the green door so doubled back once she had lost them. She couldn't take it anymore, so headed towards the green door. She grabbed the knob and found to her surprise the door was unlocked. She slowly opened it and entered.

There was no Richmond, but it was just as scary, it was a tunnel. Being Jen she decided to follow it. After about five minutes she reached the end and found a small door. She tried to push it open but it wouldn't budge. She grunted and groaned and lent her shoulder into it. It was no good. She decided to turn back but the way back was blocked. She started to panic and began banging on the door and yelling, hoping someone would help her.

Meanwhile in Pasadena, Leonard was entering his apartment after dropping Sheldon off at the comic book store when he heard a loud banging behind the closet with the door Sheldon had asked him not to open. Leonard pushed the closet aside as quick as he could fearing that Sheldon was crazy enough to hold hostages. Aa red haired woman ran over him and into the apartment gesticulating madly.

"Oh thank god I thought I would be trapped in there for ever!" she moaned dramatically. "Wait," she stopped short, "this isn't Reynholm industries."

"What's Reynholm Industries? And who are you? Was Sheldon holding you hostage?" asked Leonard.

"Who's Sheldon and where am I?" asked Jen.

"You're in Pasadena California," said Leonard.

"California! I'm in America?" asked Jen

"Well yes where did you think you were?" asked Leonard.

"I was just in London, how could I have travelled thousands of miles in no more than 10 minutes?"

"Wait lets back track a little, you're from London?" asked Leonard.

"Well yes I'm sure I've established that," said Jen.

"Well I can tell from your accent your from England but tell me If you were just in London how did you get here?" asked Leonard.

"I don't know I had just got back to work from lunch, and I couldn't help but wonder what was behind the green door that my workmates, Roy and Moss, told me not to open even though they said they'd never opened it because the last people who'd worked in IT told them not to open it because of some experiment they did with some crazy scientist…. Oh my god that's it! The green door is a gate way from London to Pasadena!" said Jen in disbelief.

"Wait. Did you say that the people who made that door were working with some crazy scientist?" asked Leonard.

"Yes why," answered Jen.

"I think that the scientist they're talking about is my roommate Sheldon," said Leonard.

Back in London Roy and Moss were just getting back from lunch and were just easing themselves in behind their computers when Roy noticed the green door had been opened.

"Oh no!" he gasped, "Jen opened the door!"

"You'd think she'd be listening to us and do what we say this time but no as soon as we say 'don't open the door' she has to open the door," said Moss in despair.

"That woman never listens to us except when it has to do with computers," said Roy angrily.

"Do you think she would have listened if we told her it was me who helped make the door?" enquired Moss.

"No that would have made her more curious and besides the only thing that's become good of that door is that I was able to convince you to invent smaller things, like the Abracadab Bra," said Roy side tracking.

"True and they have been a little less disastrous, but that's beside the point we have to go rescue Jen," said Moss sounding harried.

"Alright. It is sort of our fault that she went through the door, let me just get the machine to answer the phones while we're away," said Roy.

He connected it up and the recorded message of, "Hello IT. Have you tried turning it off and on again?" came on.

"All good," he said as he led Moss through the green door, leaving Reynholm Industries, behind.

Back in Pasadena, Sheldon burst through the door to his apartment, "Leonard I was about to tell you that I'd forgotten my wallet before you rudely took off forcing me to take the bus back and…. Leonard who is this woman?" Sheldon demanded.

"Oh this is Jen she's from Reynholm Industries," said Leonard.

"Reynholm Industries? Leonard I told you not to open the door behind the cabinet," demanded Sheldon.

"Sheldon I heard her yelling behind the door. I thought you had kidnapped her!" exclaimed Leonard.

"Why would I kidnap someone?" snapped Sheldon.

"Well considering some of the crazy stuff you've done before I really wouldn't put it past you," declared Leonard.

"That's not the point Leonard I told you not to open the door," demanded Sheldon.

"Just hold on!" interrupted Jen, "What on earth is going on?"

"This isn't your concern," said Sheldon rudely.

"Jen! Jen?" called Moss from a long way off.

"Jen?" called Roy.

Suddenly Roy and Moss burst through the "hidden" door.

"Jen you're alright?" asked Roy worriedly.

"Yeah I'm fine now tell me what the hell is up with the green door I went through?" asked Jen.

"Well ah…" started Roy.

"Moss, Roy I thought we all agreed that none of us were ever going to use that door again," said Sheldon.

"Oh look Sheldon's still alive," said Moss.

"Oh hello Sheldon, how've you been?" asked Roy.

"Irrelevant. Why'd you open the door?" demanded Sheldon.

"Well it's complicated," said Roy slowly.

"How can a little thing like 'don't open the door' be complicated?" asked Sheldon exasperatedly.

"Everyone just be quiet and explain what the hell's going on! Like why is there a door in our apartment that leads to London? And why there are three people from England in our apartment?" shouted Leonard.

"To be fair I'm actually from Ireland," said Roy.

"That doesn't matter, Sheldon tell me right now what the hells is going on?" demanded Leonard.


I hope you enjoyed my first chapter of IT vs. Big Bang. Ill update as soon as I can and in the mean time feel free to express your opinion