Turn a betrayal inside out and you found its opposite, a secret and a bond. Perhaps that was what friendship came down to: a lifelong, affectionate mutual blackmail.

Neil and Adam, two young men on the cusp of adulthood, meet one golden summer in California and, despite their different backgrounds, soon become best friends. But on a camping trip in Yosemite they lead each other into wrongdoing that, years later, both will desperately regret.

Their connection holds through love affairs, fatherhood, the wild successes and unforeseen failures of booming London, as power and guilt ebb between them.

Then the truth of that long-ago night emerges.

What happens when you discover that the friendship you can’t live without was always built on a lie?