Ruby is a trainee detective, her boyfriend Jools is a criminal defence solicitor. They find themselves on opposite sides of a murder confession when Freya Maskell walks into a police station and, without saying who it was, says only that she's killed someone.

Tony Gibson has died from a blow to the head and his body is pulled from the Thames. It emerges that Freya, a sex-worker specialising in fantasy role play, had been with him the night before her confession. The role he'd paid her to perform had involved the use of force against him and she is charged with his murder. But Ruby's procedural errors, which Jools describes in his evidence to the court, cause the trial to collapse...and raise a lot of questions about their relationship.

Freya swears she didn't kill Gibson, so who did? Whose murder was it she so nearly admitted to? Ruby becomes obsessed with Freya and is taken over by a burning desire to uncover the truth. But at what price?"

"If she plays by the rules she won't get her woman; but if she plays dirty will she lose her man?"