You can make a convincing argument that Saorise Ronan is the most consistently excellent lead actress working in films today. She came to most people’s attention as a 13 year old in Atonement. Now, 11 years later she is starring in another adaptation of an Ian McEwan book.

She plays Florence Ponting, the daughter of wealthy parents, who in 1962 has just graduated from Oxford with a music degree. She meets history graduate, Edward (Billy Hoyle) who comes from a more humble family and they start a relationship. Whilst their different backgrounds are crucial to the story, McEwan’s own adaptation avoids any of the cliches you might expect. Instead, it provides context and depth, as does the period setting with society on the brink of irreversible changes politically and culturally.

With its myriad flashbacks and slow pace, the impact of the story may have been much lessened without Ronan’s mesmerising performance. She manages to perfectly mix a bossy confidence that growing up in a privileged household brings with an innocence and naivety. It is hard to think of another actress who could pull it off so well. Hoyle is fine – though very much in Ronan’s shadow – and he didn’t quite convince me he was someone renowned for his fighting skills. Incidentally, the only other unconvincing thing in the film is the cricket match, where Edward’s non-shot is hilariously unrealistic!

The great Emily Watson as Florence’s mother has little more than a cameo, and it is Adrian Scarborough as Edward’s Dad who stands out in the supporting cast. An actor better known to me for his comedic parts, he has one particularly stunning scene with his son after the relationship with Florence begins to unravel.

This a film that sort of creeps-up on you and gets under your skin and I like the ambiguity – was Florence abused as a child, why does she change in outlook in the decades that pass after she marries Edward? The final scenes set in 1975 and 2007 provide a real gut punch, with the latter reminding me a little of the final moments of La La Land.

Rating: 9 out of 10