I have an interview tomorrow

nice way to end my vacation I must say. However this is the first time I have ever dealt with a recruiter before. I've heard the horror stories of RHT and such so I'm a little skeptic going in. It all seems good (almost too good) 30-35k pay increase from what I make now + great benefits etc.,
On to my Question.
Most interview's end with a "Do you have any questions you would like to ask us?" However seeing this is with an agency and not the actual employer, will that question come up? and if so what do you ask? I've got some questions I normally ask but I'm not sure if they'll work in this scenario.