A Close Connection tells the story of Eleanor and Henry Nightingale and Paula and Alan Walker, two very different couples brought together by the marriage of Nicola, the Nightingales' daughter, to Matthew, the Walkers' son. Elegant and successful, Eleanor has turned a blind eye to her husband's infidelities for years; Paula lacks confidence and blames herself for the death of her daughter years ago, unlike her husband Alan who is laid back and not intimidated by the lifestyle of the Nightingales. A holiday in Italy, intended to bring the four closer together, creates both bonds and rifts with long lasting effects. On their returning home, a health scare brings Eleanor's life into sharp focus and she calls on Paula, who will soon experience her own struggles, to help. Meanwhile, Nicola and Matthew's marriage is facing its own crisis point. Will these three marriages survive such turmoil?