At his mother’s New Year’s Eve party, Lucas (Tom Blyth), a young police officer, loses a letter no one was ever meant to read. Amid the backdrop of the suffocating family party, the search for the letter unlocks memories of a past he’s tried to forget: months earlier, while working undercover, Lucas arrested men by seducing them. But when he encounters Andrew (Russell Tovey), everything changes. What begins as another setup becomes something far more electric and intimate. As their secret connection deepens and police pressure to deliver arrests intensifies, Lucas finds himself torn between duty and desire. With time running out and his past closing in, PLAINCLOTHES builds toward a reckoning where everything he’s buried threatens to erupt.