When a beloved couple vanishes just before their annual Christmas party, their family fears the worst - and police must do everything from posing as the Mafia to coaxing information from threatened witnesses in order to solve a years-long mystery.

After a fun night out, Morna Brennen walks into an icy parking lot one dark Minnesota winter and disappears. When body parts begin showing up in the area, police must decipher cryptic clues to understand what happened, who did it... and why.