Jimmy questions Donna about the shocking DNA results, Alison arrives in Norway in search of Andreas Hagan, and an unexpected twist leads Perez and Tosh into the murky world of the Norwegian far right.

In the aftermath of the diving incident, the team searches for a link between the two bodies. Meanwhile, Perez must deal with the return of Donna Killick.

After the discovery of an unknown body, the search for Connor grows increasingly desperate. Perez follows Danny on a perilous journey into his murky past.

Perez issues a warrant for Connor’s arrest and looks for the motive behind his bomb-making. Sandy tries to find out what business William Rodgers had in Shetland.