Eighteen years ago, on a mission in Iraq, Captain John Milton made a reckless decision with serious consequences. But it was Major Connor Gordon who really paid the price. Now Milton is on a different mission: to atone for his past sins. A human rights activist has vanished without a trace and his dying mother is desperate to know the truth. When the mysterious disappearance leads Milton all the way to the Western Isles of Scotland, he sees an opportunity to find his old friend Connor and finally make amends. Milton is determined to track both men down, wherever his search may lead.

1969. Eloise Shepherd, one of MI6’s brightest rising stars, is working undercover in Soviet Russia as Magdalina Novikova. Her mission is to persuade nuclear physicist Stanislav Kalashnik to defect and bring his knowledge of Russian weapons back to the UK. On the verge of success, the operation fails suddenly and spectacularly. Seventeen years later, Kalashnik is chief engineer at the power plant near Pripyat known as Chernobyl. His concerns for the safety of the plant are growing. 

John Milton travels to Bali in search of a new identity, but he can't even manage the flight without finding someone who needs his help. A beautiful woman falls ill and confesses that she has swallowed packages of cocaine in order to smuggle it across the border. She has been forced to work as a mule by a Yakuza gang in Tokyo who are holding her child to guarantee her compliance. Milton decides that's unacceptable and promises to lend her his help.

John Milton has a nose for trouble. He can smell it a mile away. And when he witnesses a suspicious altercation between a young man and two thugs in a car auction parking lot, he can’t resist getting involved. Milton came to Kansas City hoping to find a way out of danger. His recent vendetta against a cartel hitman who killed his friend has made him enemies in high places. Now he needs to find the only man who can get him out of this mess. 

Before he was the Gray Man, Court Gentry was Sierra Six, the junior member of a CIA action team. In their first mission, they took out a terrorist leader, at a terrible price. Years have passed. The Gray Man is on a simple mission when he sees a ghost: the long-dead terrorist, but he's remarkably energetic for a dead man. A decade of time hasn't changed the Gray Man. He isn't one to leave a job unfinished or a blood debt unpaid.

John Milton is used to operating in the shadows, weaving his way through dangerous places behind a fake identity. Now, to avenge the death of a close friend, he must wear his mask of deception once more. Beau Baxter was brutally murdered by a drugs cartel but that doesn’t stop Milton from blaming himself for his friend’s death. With the help of a trusted team of undercover experts and Beau’s son, Milton is determined to track down the killers. And he isn't just after the man who gave the order. He’s heading right for the top.  

Billy and Charlie thought their killing days were behind them. They used to be prolific life-takers, but old age finally caught up with them. Now they are ending their days in a dismal nursing home in Blackpool, with only their memories to keep them going. Memories of murder and mutilation. But when Archie turns up at the home, everything changes. Archie is a breath of fresh air, and he puts new life into Billy and Charlie—and before long, they realise that it's time to start killing again.

Is John Milton on the path to redemption or the road to revenge? John Milton has done some bad things in his life. Very bad things. Now he’s looking for ways to make amends. But trouble always seems to be looking for him. Heading from San Francisco to Las Vegas, Milton’s solo road trip takes an unexpected turn when he picks up Jessica Russo, a young woman in distress at the side of the road. She urgently needs a ride and he’s happy to help her out. But what starts out as a simple favour quickly becomes something more sinister....

John Milton hasn't seen Elijah Warriner for three years. The last time they met, Milton's efforts to keep the boy safe didn't go exactly to plan. Now Elijah is a promising boxer, preparing for the bout that will take him to the big time. Milton decides that he will spend the week before Christmas in London so that he can watch the fight. But Elijah's burgeoning fame has brought him to the attention of old acquaintances with long memories and grudges to bear.

Ex-Special Forces operator Tom Keeler is a rambling man. He’s just passing through the town of Alencourt, France, and in less than an hour, someone tries to kill him. Nice place, nice try. But it’s a case of mistaken identity, and they picked the wrong guy. The French police can’t be trusted, except for the beautiful Cecile Nazari. She finds out fast that keeping up with Keeler is a dangerous occupation. Because someone’s preying on the weak and unprotected. Someone murderous. But they never counted on coming up against a guy like Keeler. 

Rio de Janeiro. Brazilians call it Cidade Maravilhosa - the Marvellous City - but crime festers in its favelas like cancer. John Milton is visiting an old friend who runs a close protection business guarding the city's elite. Milton offers to stand in when one of his bodyguards doesn’t turn up for work. The job? Take the wife and daughter of an anticorruption judge to a school recital and bring them back again. Simple? Not so much. The girl is snatched off the street, and Milton is nearly killed. As he recovers at a Group Fifteen safe house, he decides on two objectives.

Tom Keeler finds himself in the town of Promise, Indiana. He just needs to drop off a package, then he can get back to the Florida sunshine. But nothing’s ever that simple. The package gets stolen; things get complicated. Linda Cartwright’s a happily married woman, and then someone tried to kill her on her own front lawn. Why would they do that? Good question. Keeler’s interested, but Cartwright won’t talk about it. When Cartwright’s attacked a second time, Keeler begins to suspect that she’s in over her head. She’s a tough lady, but even tough nuts crack.

An assassin haunted by his past. Two young refugees out of their depth and in need of his special talents. John Milton is no stranger to the world's seedy underbelly. But when the former British Secret Service agent comes up against a ruthless human trafficking ring, he'll have to fight harder than ever to conquer the evil in his path. After Milton meets a refugee who lost a sister to people smugglers, he travels through war-torn Libya and the murkiest parts of Italy and France to get the girl back.

NYPD detective Jack McNeal is used to asking the tough questions. But a late-night visit from the Secret Service lands Jack on the other side of the table—as a suspect in the disappearance of his estranged wife, Caroline, a prominent reporter on the White House beat. When her body is found floating in the Potomac, Jack is overcome by disbelief and despair.

New York isn't ready for Britain's most dangerous ex-assassin.... John Milton has finally found a place to escape the bloodshed: off-season Coney Island. No tourists. No special ops. Just peace and quiet. But when a local boy witnesses a grisly murder, Milton can't resist investigating. Milton uncovers a vicious drug kingpin and a group of crooked cops from a notorious precinct known as The Alamo. Against such dangerous foes, Milton's quest for redemption could come to an end.