1)The exteriors for this story were filmed at Leeds Castle, which, oddly enough, is in Kent.   2)Mary Tamm claims to have designed the outfit she wore in this.  Not sure I'd brag on that, myself. Generally, the costumes in this were pretty good. As with "The Ribos Operation", it's the sort of thing the BBC does well. This Tamm's favorite story, as she got to play Romana, Strella and Mecha-Strella…