Here you go! As always, please review! :)
John showed Donna and the doctor the place where he had last seen the blue box. They, like him, also walked around in circles where it had been.
''So.. Doctor who exactly?'' John asked the doctor.
The doctor just looked up ''Well...''
''Mystery. Nobody knows'' Donna told him later, and John didn't talk anymore about it.
The doctor grabbed something from his inner coat.
''Look here, it's my screwdriver!'' He pointed it at John. ''It's sonic!'' The doctor pressed something on the screwdriver, and it made a strange sound and the tip of the sonic screwdriver shined in a bright blue colour.
''What does it do?'' John asked, again.
The doctor stared at John, and then, again, at the screwdriver. ''Well...''
Donna laughed loudly at them, and then quickly stopped.
At that moment John realised just how rude they were acting towards him.
''What is an TARDIS? I heard you speak about it in the café. Care much to tell me?''
''Told you he was '' Donna snapped.
''Of course i care, TARDIS stands for Time And Relative Dimensions In Space. My own grand daughter named it, actually'' The doctor said without taking his eyes from the ground.
''You have a granddaughter?'' Donna asked the doctor.
''Wouldn't you know if he had a granddaughter if you're together?''
''We are NOT a couple'' Donna replied, and John sensed she didn't like him very much.
Joh wanted to know more about this blue box. Where exactly is it from? What were they doing with a blue box? ''What is the point of naming a blue box?''
''It is not only a blue box. The clue is in the name''
''You're kidding me'' John said ''
''Me? joking? Naah. But really. The clue is in the name'' The doctor continued staring at the empty spot.
''You're really not going to find anything just staring at the ground''
''Brilliant! Amazing job, DOCTOR'' Donna screamed. ''What are we going to do NOW? We have nowhere to live and we don't even have any money''
John thought about about doing something really, really stupid. He thought about it for a moment, while the doctor and Donna screamed at each other (it was really just Donna screaming at the doctor, while the doctor just stood there).
''If you want to- you could- you could stay with me and Sherlock''
''Noo? really? Really? you're too kind my friend'' The doctor looked at Donna and she just shrugged ''I guess that's a deal then!''
''Not really'' Jon replied
''It isn't a deal if i don't get anything out of it, really''
John turned his head and looked at Donna ''Is that his favourite word?'' Donna smiled at him in return, and then walked to the doctor, and they whispered to each other for a couple of seconds.
''You let us stay with you and that Sherlock until we find the TARDIS, then you can follow us''
''Anywhere. Whenever you want. Wherever you want''
''It's really nice, actually. You'll love it. You're that kind of person.'' Donna said.
''You'll follow us in the TARDIS- how can you not understand?'' The doctor sounded annoyed.
''Nobody understands at first'' Donna said gently.
''It's a TIME MACHINE'' Doctor waved his arms around like crazy ''That can go ANYWHERE IN TIME. AND SPACE. THE CLUE IS IN THE NAME''
John wanted to not believe him, but they seemed a little strange. Not strange like they should be put in a hospital, but strange like they don't belong here. On earth. Kind off. Especially the doctor.
''So you're an alien? From, what, mars?''
''Alien, yes. Mars... No''
''Great'' John realised it would be hard to get Sherlock on it, but he wanted to know more. Was it weird? Yeah. John should probably leave the doctor, and Donna. But he didn't. They followed him to baker street in a cab and they are sleeping on the floor right now. And sherlock isn't here. And sherlock will probably ask questions that John can't answer.