After years of marriage, Joy and Alan Richards find themselves in a sexual rut. Therapist Joy is trying to find a way to keep her spark with her husband, following a cycling accident which has put their sex life on hold. Suddenly, they find themselves drawn to new people.

Alan has sex with Claire whilst Joy does the same with social worker Marvin. Alan is aroused to hear his wife's account of her evening but the pair are interrupted by daughter Laura, dead drunk after her boyfriend left her. After confessing all to her colleague Angela, Joy decides to tell Marvin about her arrangement with Alan.

Joy and Alan explain their arrangement to Laura and her siblings Naomi and Tom — who seems upset by the news. Nonetheless, Joy prepares to meet for sex with Marc but bumps into old flame Lawrence whilst keeping from Laura Jason's troubled past.

Joy and Alan go on a double date with Claire and Marc which invigorates the Richards' sex life though Alan is forced to confess the arrangement to his head teacher Janet. Joy learns that Lawrence's father has died and offers comfort but rejects his advances.

In the midst of all the turbulence in her life, Joy's regular sessions with Angela become an in-depth exploration of the secrets Joy has been hiding from everyone, even herself.

Joy and Alan face up to the seismic changes in their lives and try to decide if their choices are the right ones. After a tense encounter with Claire, a lost and lonely Joy takes a risk on love and goes on a bold journey. Meanwhile, Tom's new relationship progresses in a surprising way.