To start things off we need to pick if Eleven takes his TARDIS to Sarah because he needs help, or if she needs help.  I'm fine with you choosing that.  I can break it down some more once you've picked so we can figure out why and where.

Then, I'd like to find out what sort of a story you'd like to write.  I tend toward dark and dangerous as the destination, but I am equally open to ice cream eating contests, or dressing up like Mr. & Mrs. Smith to open a bank account to steal something from a different lock box.  I guess I tend to go dark because I think it makes the jokes funnier.  And if you don't know, Sara excels at bad jokes and worse one-liners.

The only things I'm not into are

1. the Doctor pretending not to be himself.  If they can't be the Doctor and Sarah Jane, I don't really see the point.
2. the pair of them running into each other by complete accident.  Out of all of time and space, this just doesn't feel realistic to me.

So . . . ..there are a couple of questions up there, I look forward to hearing what you think, or whatever it is you have on your mind.