You never forget the one that got away. But what if 'what could have been' is still to come?Daniel was the first boy to make Alison a mix tape.But that was years ago and Ali hasn't thought about him in a very long time. Even if she had, she might not have called him 'the one that got away'; she'd been the one to run away, after all.Then Dan's name pops up on her phone, with a link to a song from their shared past.For two blissful minutes, Alison is no longer an adult in Adelaide with temperamental daughters; she is sixteen in Sheffield, dancing in her too-tight jeans. She cannot help but respond in kind.And so begins a new mix tape.Ali and Dan exchange songs - some new, some old - across oceans and time zones, across a lifetime of different experiences, until one of them breaks the rules and sends a message that will change everything...Because what if 'what could have been' is still to come?