Murder by the Sea (2018)

Penelope & Barry Rogers: Swansea (3x5)

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The strange relationship between mother and son Penelope and Barry Rogers, with eyewitness reports of overly close contact, leading some to believe incest was a possibility, was overshadowed by a much more sinister crime. The two planned and eventually murdered Penelope's own mother Betty Guy, intoxicating her with booze and drugs before callously smothering her. A rare case of both a mother and son involved in matricide.