Is it possible to relive the best time of your life? As they approach their thirties, Alice and Julie are determined to find out.

Still recovering from a toxic relationship, Alice realises she has allowed life to become too predictable, while Julie has just ended things with the man she was due to marry. The two friends decide to throw caution to the wind; coming back to Cornwall, where they spent a long, happy summer ten years before. As they return to the same small flat in the centre of town, and seasonal jobs at the Sail Loft Hotel, Alice harbours hopes of finding Sam, the love of her life, while Julie is determined to enjoy the freedom she's been missing.

A lot can change in ten years, though, as their friend Luke - now a handsome, successful businessman - proves. Back in Cornwall himself, as his mum is seriously ill, he and Julie grow close. Alice is worried that her friend is making a huge mistake and, all-but-abandoned, starts to spend time with single mum Casey.

Sam, meanwhile, proves elusive but slowly reveals that, although he appears not to have changed at all, the previous decade has been eventful for him, too.