One of Us - Season 1 Episode 4

Claire confronts Bill over his argument with Adam on the wedding video and is told that her brother was unfaithful, which she disbelieves. She is however intrigued to find that Adam made five phone calls to Bill on his honeymoon and uncovers a terrible secret leading to the identity of the family member who paid Walsh to commit murder and then killed Walsh . Meanwhile Alistair's wife Sal gets revenge for his affair with Moira, devastating the terminally ill Bill and Juliet plays dirty when her partner in crime threatens to expose her, depending on colleague Andrew to determine her future. The mystery of the killer within the families solved the survivors combine to chart the way ahead.