Four friends as close as they come. Until a girls' weekend away leaves them with a shared secret that could destroy them all. But a secret is safe among friends, isn't it? That's what they think - until they all in turn receive a letter with the grim truth written down in black and white. Someone wants money for their silence - and quickly... With the clock ticking, the girls must work out who they can trust and who's been watching them. And, ultimately, discover what they'd do to keep the truth among friends.