These Radio 4 dramatizations of two Poirot mysteries were first broadcast in 1993 and 1994, respectively. In the first of them, a young girl is found drowned at a Hallowe'en party, and the second is about a reopened murder case, the apparent killer having long ago been convicted and since died.
After the success of his first assignment from the UNICORNE agency, fourteen-year-old Michael Malone is given another unexplained mystery to solve. When UNICORNE detect strange goings-on in a comic book shop, Michael is sent to investigate - a task which is made all the more difficult by allies he can no longer trust, and an enemy he can't actually see .