Tango One - Stephen Leather

In different parts of London, three recruits prepare for their first day at the Metropolitan Police's training centre at Hendon. All three had succeeded in getting into the police in spite of weaknesses.

But on their first day, the assistant commissioner announces that he wants them to join a team of undercover detectives. Their brief? To become criminals; to work their way up through whatever gangs they can get access to, and to collate evidence against the criminals they come across.

Their target? One of the world's biggest drug dealers. Den Donovan, alias 'Tango One' - number one on HM Customs and Excise Most Wanted list.

Three years later all the recruits are getting close to their target. Too close, perhaps, to remember the rules.

But Donovan has more than the undercover cops to worry about - his wife and accountant have stolen $60 million from him, a Colombian gang is after his blood and he has to bring up his young son alone.

STEPHEN LEATHER WRITES

I've always been intrigued by the fact that major criminals often turn out to be family men, too. They break the law, they do bad things, but they're also somebody's son and more often than not they're somebody's father, too.

In Den Donovan I wanted to create a villain who has a very human side, struggling to bring up his young son while at the same time trying to hold together a criminal empire that's coming apart at the seams. I also wanted Donovan to undergo some sort of redemption, if not to see the error of his criminal ways then at least to realise that some things are more important than money.

I've also always been fascinated by the sort of people, men and women, who are prepared to work undercover. Villains, until they get caught, tend to have much better lives than their law-abiding counterparts. They live in better houses, drive better cars, eat at better restaurants and, truth be told, get to sleep with prettier people. It takes a particular sort of person to work undercover and not be tempted to switch sides.

Tango One is a coming together of the two themes. Three undercover cops are sent against Donovan, and each, in their own way, becomes seduced by his charisma, leading them to question what they are doing.

It turned out to be a difficult story to write, mainly because I wasn't sure how it should end. I guess I too became seduced by Donovan and didn't want him to end up behind bars!

After about six months writing the novel, I turned to my good friend and fellow Dublin-based writer Glenn Meade for suggestions on where to take the plot, and as always he was a great help. Sometimes writers can get too close to their work and they need a dispassionate outsider's view to keep them on the right track. Anyway, I'm proud of the way that Tango One turned out, and I think it's one of my best thrillers.