Maya, By Alastair Campbell

What was it Gordon Brown once said to Tony Blair? "There is nothing that you could say to me now that I could ever believe." Few lines in literature, let alone politics, have conveyed so absolute a sense of betrayal, and these words came to me as I put down Alastair Campbell's second novel, a tautly paced thriller about a man's betrayal of his closest friend.

The temptation would be to look for further Blair-Brown parallels, but the only familiar character who emerges, somewhat creepily, is the former spin doctor himself, through the voice of the narrator. This is Steve Watkins, a married 29-year-old logistics executive from Acton who happens to have been at school with Maya Lowe, a beautiful actress who is hitting the big time. Inexplicably, they remain close friends while their paths diverge, he becoming her "rock" as her career shoots off on a Leona Lewis trajectory.

How a close friendship is affected by the pressures of time, other relationships and the divergence of fortune is a fascinating and complex subject. Campbell tantalisingly opens that particular costume box but then drops the lid shut and instead bludgeons home the "them-and-us" theme. So Maya lives in a luxury home in Little Venice with a chauffeur-driven Mercedes and all the trimmings, while Steve's life is more David Brent: the grinding commute, an office in Heathrow, a company Peugeot.

Material trappings serve as shorthand for characterisation in this book, which leaves us wondering what it is that Maya sees in our desperately bland narrator. I couldn't help picturing Campbell as Steve, all the more so when he develops an impressive talent for manipulation and casual fibbing. As Maya's stardom grows, Steve becomes ever more determined to protect her. Convinced that her husband, Dan Chivers, a smarmy chat-show host, is up to no good, he begins to follow him. Alarm bells ring in the reader's mind as this obsession develops, getting ever louder by the time Steve is having Dan professionally spied on. Any sympathy we had for Steve evaporates as he embarks on a bizarre series of actions which can only lead to disaster. He lies to his wife, his colleagues, to Maya and of course to himself: Campbell details with uncanny familiarity the panic of a man who tells one lie to cover another.

The narrative rattles along at a pleasing pace and if the denouement is not totally surprising (four of my six predictions came true), it is at least worth reading on for a scene which, I put a tenner on it now, will scoop this year's Bad Sex in Fiction Award. Some of the best passages parody rolling news channels, in which Campbell captures the breathless blather of a breaking news story. (Presenter: "What do we know about the substance here, about what Maya will be saying?" Reporter: "Well, we don't know her exact words yet...")

After dealing with mental illness in his first novel, Campbell now seems to be seeking catharsis for his life as a spin doctor. He exposes himself most through the character of Maya's agent, Nick Sheldon, a master of media manipulation who waits for a big news day to "bury" a bad story (pace Jo Moore) and is constantly bestowing favours or punishments on different newspapers (Evening Standard good; Sunday People bad). The most revealing insight must be when Sheldon instructs Maya's elderly father, at whose house she is hiding, to tell the press, "She is not at home. She is with friends." The old man delights in the deception: "Not a lie as such, but put them off the scent. Not at home – true, not at her own home that is. And with friends – what better friends does she have than me and Anna [Maya's mother]?"

Campbell appears unafraid to turn a spotlight on his own dark arts, and in one dialogue between Sheldon and Steve he even runs through the moral pros and cons of spin. His own beliefs remain obscure, but through two novels Campbell has already spoken volumes more truth than he ever did in politics.