Only to Sleep is the third Philip Marlowe novel written by someone other than Raymond Chandler and while the authors of Perchance to Dream and The Black-Eyed Blonde both found freedom to play with Marlowe and explore his potential, it is Lawrence Osborne who has run the furthest with the source material.

The novel opens in 1988, with Marlowe living in retirement in Baja, Mexico. He is 72, and enjoying a leisurely life in the sun, when he is asked to take on one last investigation into insurance fraud.

A Reagan-era Marlowe unlocks an aspect that Chandler never considered. His Marlowe was ageless (he wrote that the detective was around 38 and ‘no older today’ in one letter), whereas Osborne’s is now frail, inviting us to question how heroes deal with older bodies and brains. When we first meet him he is trying to preserve an old, familiar era, wearing dated suits (‘When did you get that suit made? D-Day?’ one character asks him), speaking ‘Ice Age’ slang, and stuck with his own sad memories (‘The unfortunate can die anywhere and they often looked like children asleep, with faces I had known when they were living’). The past haunts him, and yet the distance of retirement has put his morality into a new perspective (‘I was in my twenties then and full of disbelief about nobility and charm’). It will come as a surprise that Osborne’s Marlowe actually has friends and companions. He even owns a dog.

Tempted by the opportunity to ride out one last time, Marlowe agrees to investigate the death of Donald Zinn and the role of his beautiful wife, Dolores. But the exertion of it reveals physical and mental decline. He isn’t the tough guy he once was and his judgment is slipping (the only explanation for his infatuation with Dolores). By the end of the novel, the carefully constructed life is no longer a bulwark against reality:

It was as if age had finally come crashing down upon me… I was old and they were young, and they had grace where I had none.

Readers expecting a familiar Marlowe may be disappointed by this book. The narrator’s voice is engaging but it misses the mark. The snappy exchanges we anticipate are sown too thinly. Marlowe’s motivation is unclear, inconsistent and unconvincing; and the bitter cynicism about LA and it’s inhabitants is deliberately absent.

But these omissions are not fatal and, when recognised for what it is — a gripping, elegantly written crime story about age and decline — Only to Sleep stands up with the best of them. Of course it’s unlike anything Chandler would have written — he had different concerns — but with its blend of mystery and humanity it’s exactly the sort of novel he would have been pleased to inspire.