Mario Vargas Llosa's new novel concerns the last days of the Dominican dictator Rafael Trujillo before he was assassinated in 1961. Mixing fiction and fact, the book offers a masterly portrayal of this most emblematic of tyrants, who ruled his country for 31 years. It is a miracle that this emperor wore any clothes at all, because he spent most of his time fornicating in bed. A serial philanderer, he sent his ministers on missions abroad in order to seduce their wives. Known as the Goat, the Benefactor, the Father of the New Nation, Trujillo thought he ruled by divine authority and became godfather to hundreds of babies a week. If his followers fell out of favour, they were fed to the sharks - or his closest associates would read about their resignations and disgrace in the press.
Against this menacing backdrop unfold three overlapping stories told from the perspective of Trujillo, the seven assassins and Urania Cabral, the daughter of one of Trujillo's inner circle. The novel opens in 1996, as Urania returns to her homeland after a life of self-imposed exile. She left the country aged 14 and has come back to confront her ageing father about his past links with the regime. As the novel progresses, the narrative moves back and forth in time, culminating in the chilling denouement, where the teenage Urania comes face to face with the Goat.
This is an impressively crafted novel, teeming with characters and Vargas Llosa's trademark style, but the switches between present and past, sometimes in alternate sentences, can be confusing. The scenes of degradation have a voyeuristic appeal. If the Urania story is less successful and the least convincing strand, there is more than enough incident and drama to keep you hooked. The set pieces are magnificent - the stake-out, the shoot-out and the showdown - but it's the small details that you recall: the smell of cheap perfume sprayed on to electric chairs to conceal the stench of urine, excrement and charred flesh. Or the scent of almond blossom that accompanies the acts of abasement at Mahogany House, where Trujillo deflowers young virgins.
One of the rich ironies of the novel is how the assassins are ardent Trujillistas themselves. Trujillo is transformed into a monster by the adulation and acquiescence of the masses. But in the end, Trujillo himself is as oppressed as his own people - oppressed, that is, by his own humanity. He is vain (he would never permit himself to sweat in public), obsessed with punctuality (he never rises a minute before or after 4am), in poor health (increasingly impotent and incontinent) and paranoid. As the head of his secret service says: "I can't have friends - it would compromise my work."
So where does this stand in the Vargas Llosa canon? Some say it is his best novel yet, but I am not so sure. It is certainly his best novel for many years, but it cannot match Aunt Julia and the Scriptwriter for spectacular exuberance and inventiveness, nor The War of the End of the World for epic sweep. In fact, the language of the book is strangely flat and the imagery muted. It is hard to know whether these are faults of the translation or whether they are a deliberate ploy to tone down the more excessive violence. I'm not complaining too much. Even if this is not a great novel, Vargas Llosa is still a great storyteller.
Sebastian Shakespeare is an editor on the London Evening Standard