An aging couple (Tom Courtenay & Charlotte Rampling) happily planning their 45th wedding anniversary party is nudged softly off the rails when word is received that the body of his first young love, who died in a hiking accident in the Swiss Alps decades ago, has been discovered, perfectly preserved in the glacial ice.

It’s quite remarkable filmmaking, really. This is director Alexander Haigh’s beautifully observed, gently explosive examination of a long-term, “good” marriage and the tender falsehoods that sustain it. The film contains no grand gestures, no big moments, yet the impression it leaves is huge. Marriages, even long and solid ones, it is telling us, are still made up of two individuals.

The film is completely without contrivance or manipulation. It’s the kind of movie whose excellence you don’t really realize until perhaps hours after the end credits roll. It will stay with you for days or even weeks afterwards.

Courtenay does some of his best work, understated and subtle. But this is Rampling’s movie, as we watch her move from domestic contentment to earth-shattering realization. The absolutely devastating final ten minutes shows why she is one of our best actresses working today, of any age.

Be warned: This is a film for grown-ups. It requires your attention. Its rewards may escape today’s attention-deficit audiences. (95 min)