Before She Knew Him by Peter Swanson
In Before She Knew Him, artist Hen and her husband Lloyd have just moved to the suburbs to get a new start after her recovery from a manic episode during which she became obsessed with the unsolved murder of a young man named Dustin Miller. When their new neighbors, Matthew and Mira, invite them over for dinner, Hen is shocked to see a trophy in Matthew’s office that was taken from the scene of Miller’s murder.