 The voice of the bomb (which is credited to "Kim Bread") is actually  the voice of John Cleese (qv), according to Douglas Adams (qv).  Adams said that Cleese was working for scale and they could not put  his real name in the credits. Cleese had previously (and  unsuccessfully) tried to get his name credited under this pseudonym  in _"Doctor Who" (1963) {City of Death: Part Four (#17.8)}_ (qv),  also written by Adams.