In 2012, Charlotte arrives at the flat of a recently deceased friend. She was one of seven students who once lived there. Memories are triggered of 1965 when they all met for the first time. Full of idealism and potential they embark on a journey of discovery, love and betrayal.

In 2012, Charlotte is joined by two former flatmates to clear the flat. Back in the late 60s, Lilly faces a terrible personal crisis. And at a violent anti-Vietnam war demonstration Jack and Victor face a challenge that will define their perceptions of each other forever.

The action moves to 1973, and the nation is in turmoil, stricken by industrial action. Jack is working as a trade unionist, but compromises his principles to help his father's flagging political career. Charlotte realises the time has come to leave Jack - and the flat - when her mother's mental condition deteriorates, and Orla faces a painful decision when her brother turns up on her doorstep, on the run from the IRA.

The year is 1982, and as Britain and Argentina go to war over the Falkland Islands, Jack is fighting his own battle with heroin addiction, prompting the former flatmates to help their friend detox. Meanwhile, Lilly receives devastating news, and Charlotte's mother places increasing demands on her daughter, not least when she turns up during an acute manic phase. Penultimate episode of the drama, starring Claire Foy, Sam Claflin, MyAnna Buring and Lee Ingleby.

As the action moves to 1990, Jack decides to sell the flat, so Orla organises a final get-together for the friends. Victor is the last to arrive, bringing with him a revelation that stirs up old ghosts and secrets from the past - but that proves to be only the beginning in an evening of shocking confessions and angry truths. Finally, back in 2012, the sixth flatmate arrives to help - and it is clear that the consequences of that day 22 years earlier still haunt them. Claire Foy, Sam Claflin, MyAnna Buring and Lee Ingleby star.