4/6 In 1979, the seven flatmates come together to celebrate Alan and Lilly's wedding.
BBC HD & BBC Two
3/6 In 1973, London is targeted by an IRA bombing campaign and Alan makes his play for Lilly.
2/6 Back in the late 60s, Lilly faces a terrible personal crisis.
BBC Two Wales
BBC HD & BBC Two except Wales
1/6 Charlotte arrives at the flat of a recently deceased friend whom she met as a student.