The RMP begin their desperate search. Tilbrook takes Markham to visit an important prisoner. Alison confides in Honor about her affair and can't go on with her pregnancy.

Cast: Jeremy Neumark Jones, Jessie Buckley, Stephen Campbell Moore, Essie Davis, Richard Dillane, Amanda Drew, Ouidad Elma, Amira Ghazalla, Tom Glynn-Carney, Louis Greatorex, Aymen Hamdouchi, Andrew Havill, Michael MacKenzie, Ben Miles, Kal Naga