In John Banville's fifteenth novel, Ancient Light ageing actor Alexander Cleave remembers the passionate, tender affair he had with the mother of his best friend Billy Gray.

As the story begins, the young Alexander is getting up to the usual boyish stuff with his friend. Then one day, he has a fragmented vision in a multi-sectioned mirror, of Billy’s mother, Mrs Gray - unclothed - in her bedroom. This leads to their first intimate encounter in the laundry room of the family home.

Further assignations between the young Cleave and Mrs Gray take place in the family station wagon and at an abandoned old cottage. The whole business is a kind of extravagant boyish fantasy - this is Catholic Ireland of the 1950s, yet Mrs Gray cannot resist her son’s best friend. Somehow they get away with the affair for the length of a summer, unnoticed by Billy and his short-sighted optician father.

Meanwhile, back in the present, the actor is remembering his daughter Cassandra who committed suicide by throwing herself from a cliff at Portovenere, on Italian’s Ligurian coast. Cassandra's story already featured in two previous Banville novels, Eclipse and Shroud.

So we are talking about a trilogy, but the new novel is perfectly self-contained and it is not necessary to have read the previous works. Unresolved grief for his daughter - felt both by himself and by his now distant wife Lydia – leads Cleave to take a trip to Portovenere in the company of a the young actress Dawn Devonport. Cleave and Dawn are the leads in a film that is being shot in London.

Banville’s poetic story weds Proustian recollections of times past with memories of Cassandra’s tormented life and the present-day traumas of his travelling companion, Dawn. There is an eerie, Gothic grace and pace in the Italian scenes, which take place in winter.

As in his 2005 Man Booker-prize winning The Sea, Ancient Light is partly set in Rossmore, to where Mrs Gray decamps for a fortnight’s family holiday. Rossmore is a fictional recreation of Rosslare of 50 years ago, where Banville himself spent summer holidays with his family. The Sea will shortly begin filming there, in fact.

There was a trend some years back whereby critics would list out an amusing list of near-derelict words which Banville had worked into novels like Eclipse and Shroud. In Ancient Light, once again, you get in no particular order: maculate, ticking (as in mattress), horrent, spatulate (as in fingers), imbricated, leporine, aurate, panopticon, concumbence, fermata. But it's okay, you can skim over these words, if you don't feel inclined to chase down their precise meanings.

Typically, Banville sits back and takes a good look at things. There is a beautiful description of the wraith-like stream of steam from a boiling kettle. As always, the author paints the weather, straining to get the absolute picture of a river, a sea, a fall of light. Thoughts, ideas, feelings are spliced for their every nuance, and there is a striking maturity of reflection. But nothing is so precious that it can’t be interrupted, to tell us what kind of sky is up there above our heads.

A recurring theme is how memory plays tricks on Cleave. At one point, the actor thinks his teenage affair with Mrs Gray took place in April. “Winter sunlight – no, no, it was summer, for heaven’s sake, keep up”, he remonstrates with himself in one passage. But if we have lived long enough, we can recognise Cleave's feelings about memory and its beautiful deceptions.

Paddy Kehoe