I thought Gary Martin was great. It's his loud and over-the-top performance that makes the Epideme character stand out so much. I don't think a subtler performance would have been right for this character. It's a good episode - one of my favourites from season VII. My only problem with the episode is the cop out 'to be continued' caption that appears right at the end, which is just there to assure us that Lister is going to get his severed arm back.