I had been looking forward to The Catalyst a lot, given my recently renewed enthusiasm for Leela. Well, it's a great story for Louise Jameson, who gets to play lots of different roles (she's pretty terrible at doing Tom Baker, but I don't mind) but I didn't like the plot; I generally hate the ones that depend on previously untold adventures, and here we have the Doctor and Leela visiting Lord Joshua Douglas, apparently a former companion of an earlier Doctor. And it never really became clear what was going on; horrible deaths happening all over the place but we never quite got to the bottom of exactly why. ( )