A raft adrift in Swedish waters holds a grisly cargo: two dead Latvians who have been horribly tortured. Arriving to investigate from Riga, Latvia’s capital, is an enigmatic police major. He reports back to headquarters and then disappears. After learning of the major’s death, Wallander goes to Riga and meets his widow, Kristina (Rebekah Staton, “Tess of the D’Urbervilles”). Together, they become embroiled in a desperate search for files that may document high-level corruption that threatens to make Wallander and Kristina the next torture victims — and corpses.