Iona

After Bull kills Iona's abusive partner, they flee Glasgow to hide on the Isle of Iona. They drive away with guilt pressing on Bull as they plan a new life away from their past. Upon arriving on Iona, they burn the partner's body inside their car, an act that haunts Bull.

They arrive unannounced at Daniel's home on the island, seeking shelter. Daniel, Iona's former adoptive father, explains that his wife Helen had died ten years earlier, and he agrees to let them stay. Iona reflects on the long, complicated history with Daniel and Elisabeth, who is now part of his life.

The island's Celtic Christian community welcomes Iona back with open arms. Elisabeth, Daniel's daughter, has married her childhood sweetheart Matthew and has a paraplegic daughter, Sarah. Iona and Elisabeth awkwardly reconnect after years apart, while the community adapts to new dynamics.

Matthew decides to take Bull under his wing, guiding him as he adjusts to island life. Sarah begins flirting with Bull, complicating his feelings and drawing him into new relationships. The two families navigate the changing loyalties on the island.

Daniel and Iona rekindle their past romance amidst the island's quiet rhythm. Their affair adds tension to Iona's present relationships and to the fragile balance within the family. They must conceal their renewed closeness as the island life continues around them.

After church, Iona shares that her mother moved to the island with a boyfriend to overcome addictions, but the boyfriend left them to fend for themselves. Bull's curiosity about the community's faith grows, and Iona chastises him for pressing too hard. The spiritual tensions in the household deepen as faith and family history intersect.

Bull goes to Matthew's church and prays, confessing that he killed his 'father' and seeks forgiveness. The moment is heavy, and Matthew is left stunned, unsure how to respond. Iona arrives soon after to support Bull but remains wary of the consequences.

News of Daniel's seizure and collapse shocks the house. He dies soon after, leaving Elisabeth grief-stricken and Iona with renewed guilt about the past. The community mourns, and the atmosphere on the island grows heavier.

Elisabeth stays with her father's body, and the sisters' relationship with Iona is tested by the past. Iona asks Matthew about Bull's confession, but Matthew dodges the question and tells her to speak with Elisabeth. The tension rises as the family navigates loss, secrets, and forgiveness.

Sarah takes Bull to her family's barn and they have sex atop a haystack, but Bull leaves abruptly. Sarah struggles to get down, eventually only briefly managing to stand before collapsing, leaving her shaken. The scene strains the fragile boundaries within the island's close-knit circle.

Iona returns to Daniel's house and finally speaks honestly with Elisabeth, who confronts Iona about her sexual relationship with Daniel and Bull's true paternity. They begin to rebuild a sisterly bond, but their moment is interrupted when mainland policemen arrive, summoned by Matthew. Iona slips away to find Bull, seeking news or forgiveness.

The policemen pursue Bull as he runs from the island's mainland authorities. Overcome by guilt and despair, Bull jumps off a cliff into the sea, choosing death over exposure. Iona learns of his death soon after, and the island's grief becomes palpable.

Iona reaches the beach to find Bull's lifeless body and cradles him in her arms. The killing, guilt, and loss converge as Iona mourns the son she thought she would always protect. The story closes on Iona's quiet, devastating vigil.