Harry's ex-girlfriend, Penny Harris, is found dead after an unusual car accident. Nikki takes on the case – which initially looks like suicide – while DCI Ambrose learns that Penny may have been having an affair. Nikki's post mortem produces a devastating revelation for Harry. Leo works on the elaborately staged apparent suicide of conceptual artist Jimmy Triangle. An anonymous video puts art critic Seth Jewell in the frame. But Leo isn't convinced and he starts to realise that this death is an artwork in its own right.