A newlywed couple steps into the sauna in their deluxe honeymoon suite - and never steps out again. When another couple is killed while boarding their honeymoon flight to Rome, it becomes clear that someone is targeting honeymooners. FBI Agent John O'Hara is deep into the case, trying to figure out who this deranged killer is. At the same time, Special Agent Sarah Brubaker is hunting another ingenious serial killer, whose victims all have one chilling thing in common. As wedding hysteria rises, John and Sarah work ever more closely to decipher the logic behind two rampages.