In the gritty streets of London, a tough and unconventional unit of the Metropolitan Police, known as the Flying Squad, specializes in tackling violent crimes and armed robberies. Led by the unapologetic and old-school Detective Inspector Jack Regan, the squad operates on the edge of the law, employing questionable methods that often draw the ire of internal affairs. Regan, a cop with a questionable moral compass and a disdain for authority, relies heavily on his intuition and the staunch loyalty of his team, especially his right-hand man, Detective Constable George Carter. Together, they work to stay one step ahead of the city's most dangerous criminals, knowing full well that their brash tactics could lead to serious consequences.

The squad faces a heightened challenge when a series of audacious heists leads them to a particularly ruthless gang, whose precision and brutality indicate they are no ordinary criminals. As Regan and Carter dig deeper, they uncover a connection that personally implicates Regan, threatening the core of his career and personal life. In the midst of this, Regan juggles a volatile romance with a colleague, adding to the mounting pressure. The boundaries between right and wrong blur as the pursuit becomes increasingly personal, pushing Regan to the limits of his resolve and putting the entire squad's future on the line in a high-stakes confrontation with the criminal underworld.