NYPD Detective Tommy Conley travels to Sweden via a special arrangement with his department in the hunt for a serial killer. There, he observes and advises the Stockholm PD as he suspects a connection between a series of murders in New York and a death in Sweden.

Once in Stockholm he is paired with Mikael Eklund, a Swedish cop who is not too keen on American culture. Despite their differences, the two detectives work together to get to the bottom of the mysterious killings and stop the killer-at-large.