Lots of you think that Claire Peacock did it - and the more I think about it, the more I'm hoping that she did.

After all, Claire was a friend to Tracy in the Charlie Stubbs' days, and Tracy took her for a fool, saying that she had 'the personality of a frying pan'.
I'm just hoping that if it was Claire who attacked Tracy, that she gave her a wallop around the head with that frying pan too.
Cue Cluedo: "It was Mrs Peacock, in the Barlow's back yard, with the frying pan, your honour!"
