Reykjavik, Saturday night

He offered her another margarita, and, as he returned from the bar, he carefully slid the pill into her glass. They were getting along fine, and he was sure she would give him no trouble...

48 hours later

A young man is found dead in a pool of blood. There is no sign of a break-in at his flat. The victim is found wearing a woman's t-shirt, while a bottle of Rohypnol lies on the table nearby.

Detective Elinborg, already struggling to juggle family life and the relentless demands of her job, is assigned the case. But with no immediate leads to the killer, can she piece together details of the victim's secret life and solve a brutal murder?