A multi-talented actor/director/writer/producer, all obituaries are making much of Letts' impressive Who credits, however few are saying more about his multitudinous achievements  outside the show. Letts also produced Moonbase 3, The Tripods, Katy and many BBC classic serials.

Apart from producing the Pertwee era of Who, he directed The Enemy of The World, multiple credited stories plus filling in uncredited on Inferno (following Douglas Camfield's heart attack) and Eastenders. He wrote under psydonym for the show, and created some of its first audio adventures. If all that wasn't enough, he appeared uncredited in multiple episodes and his acting career included Scott of the Antarctic. He was also tapped on the shoulder to return as "executive producer " ( a role which otherwise did not exist until the revival in 2005) to oversee season 18. And he proved to be one of the most interesting interview subjects in the recent DVD releases! A 2004 interview is available on the BBC site.

Robert Seulowitz's Ratings Guide pre-revival essay Who Made Who? rates him as the second most influential person in the show's history. And he is only out of first place because of the presence of Robert Holmes, Letts' favourite writer for the show. We won't see his like again.