With tight security in the prison cell, including three locked doors and Dwayne and JP on the scene, how did a murderer manage to slip through undetected? There's no shortage of suspects, including the victim's angry wife Mae and his vengeful brother Paul, so they've got their work cut out for them.
Humphrey's father Martin also arrives on the island to speak to his son. Their relationship isn't the best, but can they put their differences aside and have a happy reunion before the series is out?
Death In Paradise, BBC1, 9pm
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