The part of Liz Shaw was given to Caroline John, who was recommended to the outgoing production team of Peter Bryant and Derrick Sherwin by James Cellan Jones. Although John had been working regularly on the stage (including for the National Theatre Company under Laurence Olivier), she was frustrated that she had not gained any TV roles. According to several DVD releases in the Doctor Who series and interviews with the actress herself, John had taken the dramatic step of having herself photographed in a bikini and sent the picture around to BBC producers. The photo ended up on Bryant's desk.