How will 'Life on Mars' end?

We love Life on Mars. Along with 'Doctor Who', it's been appointment-TV that we'll stay in to watch each week. And on Tuesday it finishes, it will be the last episode. And the big question is - how will it end? Has Sam been in a coma or has he really travelled back in time? I suspect the answer isn't going to be quite that simple...

Although we'll be glad to finally find out what happens to Sam, we're going to miss the show. For once, this is a drama show that really is quitting while it's at the top of it's game.