The Massacre of St Bartholomew's Eve - Interview with Donald Tosh

Donald Tosh was credited as co-writer on "Bell of Doom" because he supplied the final scene introducing Dodo. (Tosh wrote the final draft scripts of all four episodes, amending John Lucarotti's originals extensively. He was credited only on "Bell of Doom" because during production of the first three episodes he was still on BBC staff as Doctor Who's story editor.)