UNDER THE RADAR SECRETS OF A SWEDISH SERIAL KILLER Movie Trailer HD - Plot synopsis: A gripping new true crime docuseries that premieres exclusively in the UK on Viaplay, Monday, 7 October. Follow investigative journalist John Mork as he unravels a cryptic message from notorious Swedish serial killer Peter Mangs. Mork's investigation, aided by ex-secret service operative Jim Rathmann and a team of experts, delves into unsolved murders in Florida, using a chilling sheet of music as their guide.