Commission & omission

When Chloë Carrington, successful but predatory gallery owner of a North Yorkshire gallery, is found dead the morning after a Private View, first to come under suspicion is Annabel, the pregnant, soon-to-be-wife of wealthy ex-criminal Ed Hetherington.
Second is publicity-shy artist Ivo Kinnersley whose exhibition it is.

Despite a multitude of motives, and many witnesses, evidence to convict either proves elusive. The discovery of a new lead coincides with Ed’s fortieth birthday, interrupting a weekend of celebrations during which DI Luke Darbyshere learns that Ivo Kinnersley has not only already escaped one murder charge, but also shares a past and a secret with the woman with whom he wants to spend the rest of his life.

(Prediction Fiction participants might be pleased to know Pettinger plays a part in this.)