I wrote one page of planning for TVC. When I say planning I mean something like 'If she does A then B, but if she does C then D'. I like the E idea better. (I sound like a Yorkshireman don't I!)
I did have two of the characters follow a bad guy and another two characters follow a different bad guy. But then I decided that one gets killed, the other vanishes, so the characters realise that someone is listening in on their telephone conversations.