Some installments in the series were spun off into full-blown series. Probably the two best-remembered examples of this are "", which was produced as a one-off in the "Play for Today" strand in 1975 and three years later became a series for Thames Television, again with Leo McKern. Alan Bleasdale's "The Black Stuff", was a single play broadcast on BBC2 in January 1980, which was developed into "Boys from the Blackstuff". It was never part of the "Play For Today" strand, although it was repeated on BBC1 later that year as a single play. Other offshoots were "Gangsters", "Headmaster", and a single series of science fiction-based plays styled as "Play for Tomorrow". Towards the end of the run, three plays set in Northern Ireland were written by Graham Reid. Known as the Billy Plays, they starred Kenneth Branagh as Billy Martin in his first acting role following his graduation from RADA.