Shetland

Episode 4 (4x4)

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Perez and Tosh are warned to stay away from Mathias Soderland by the Norwegian Secret Service, who tell them they're meddling in an operation they don't understand. With Soderland their prime suspect for Sally McColl's murder, Perez and Tosh won't be bullied. However, their investigation is suddenly derailed by a shocking discovery.