House of Mortal Sin

Jenny Welch goes to the church after hearing that her friend Bernard Cutler has become a priest. She hopes to find him and speak privately, but the man at the confessional is Father Xavier Meldrum, not Bernard. She warns Meldrum about the abortion drama with Terry and then leaves, unsettled by the encounter.

That same night, Meldrum gains entry to Jenny's flat and assaults her friend Robert, whom he mistakes for Terry. He leaves Robert unconscious and the man is taken to hospital for treatment. His assault marks the first crack in his outward civility.

The next day, Meldrum invites Jenny to his presbytery, which he shares with his frail mother and Miss Brabazon. During the meeting, he reveals that he taped her confession to blackmail her. Jenny realizes the extent of his manipulation.

Jenny tells Terry about Meldrum's actions, and Terry tracks him down to threaten him. The confrontation escalates as Meldrum responds with intimidation, setting the stage for further violence.

Meldrum bludgeons Terry to death with an incense burner and buries him in a freshly dug grave in the churchyard. The body is then hidden as Meldrum returns to his routine, presenting a calm exterior to the world. The murder marks a turning point in his crusade against perceived sinners.

Later, Meldrum murders Robert in hospital, delivering another fatal act under the cover of his religious rhetoric. The hospital becomes a scene of a chilling crime that deepens the conflict around Meldrum's actions.

Jenny's sister Vanessa answers a threatening phone call on Jenny's behalf and goes to the presbytery, where she encounters Mrs Meldrum. She begins to sense the danger associated with Meldrum's influence.

Meldrum arrives at the presbytery and strangles Vanessa. Brabazon later urges Meldrum to complete the pattern by removing his mother as well.

Brabazon consoles Meldrum and reveals that she has always loved him, and they hatch a suicide pact to be together forever. Brabazon fatally stabs herself, but Meldrum hesitates.

Under Brabazon's urging, Meldrum murders his frail mother under the pretext of a mercy killing. He continues his manipulative silence to maintain control over the situation.

Bernard discovers the bodies of Terry and Vanessa and confronts Meldrum, who tries to deflect blame and claims Brabazon acted out of love. The confrontation strains the fragile truth further.

Meldrum persuades Bernard to help cover up the crimes for the good of the church; Bernard reluctantly agrees and leaves, signaling the start of a grim conspiracy.

After Bernard leaves, Meldrum silent-calls Jenny to confirm that she is at home, then puts on a cloak and steps out into the night, disappearing from view.

Meldrum dons a cloak and steps out into the night, suggesting he remains free as the events leave the audience unsettled about his fate.