Merrily, Merrily (S07E01)

Laurence has arranged a reunion with his old university chums Callum and Darren at a remote lake. It’s not quite what they were expecting, and Darren has even brought along his new girlfriend. But a lot of water has passed under the bridge since their college days, and as they strike out across the empty lake, the conversation takes them into choppier waters. (BBC iPlayer)