Every winter, the Tender family make a pilgrimage to the orchard of elderly Aunt Alice (Phyllis Burford) for the apple harvest.
Dinner is interrupted by the arrival of Damian Treloar (Brian Vriends), the recently divorced ex-husband of Betsy's daughter Anna (Eva Hamburg).
Wily and unorthodox Inspector Toby (Max Cullen) and his bewildered new assistant Detective Constable McClinchy (Tony Harvey) arrive to investigate.
The suspects include Anna; Aunt Alice; Betsy; her meek husband Wilf (Neil Fitzpatrick); their loyal son Chris (Scott Higgins) and his wife, nurse Susie (Rosey Jones), who feels oppressed by the family; Chris' longtime friend Nick, a jealous academic specialising in psychology (Stuart McCreery) and his de facto partner, Jill (Helen O'Connor), an editor who was recently working on a book with Damian; and a single mother who lives across the street, Theresa (Lynda Gibson).
Also in attendance are another couple who are friends of the family, Kate (Catherine Wilkin) and Jeremy (David Cameron) and their young daughter Zoe (Caroline Winnall).