Based on the iconic character from best-selling author Olov Svedelid, detective Roland Hassel is determined to uncover the truth about his mentor's death in this thrilling and action-packed series. When Detective Roland Hassel's (Ola Rapace, Crimes of Passion, Skyfall, Wallander) father figure and mentor, Yngve Ruda, is brutally murdered in the middle of the street in Stockholm, he decides to conduct his own under-the-radar investigations. Hassel's obsession with the case soon affects his personal life as he struggles to keep hold of his family - girlfriend Daniela (Aliette Opheim - Patriot, Thicker Than Water) and her daughter Vida. Gathering those closest to him to form the "Triton" police unit, Hassle soon finds himself in a twisted spiral of corruption - which leads all the way up to the top political powers in Stockholm and Brussels.