Today, I received the first season of Whodunnit
in the post. The first season (1972) was hosted by Edward Woodward, later seasons by John Pertwee. John Pertwee it seems appeared as one of the panel on at least some of the first season episodes.
I am now going to watch a couple of episodes, pen and paper in hand to write down clues. Hopefully I might be able to solve at least one or two of the Whodunnits during this season.