Mark Hammond is an ex-gangster who wants to forget his past and live honestly with his wife and little son. Everything goes horribly wrong when London's most vicious criminal, the organized crime boss Charlie Jolson, decides that he needs Mark's services and obtains them in a twisted and cruel way: Mark's wife is murdered, he is framed for this murder, and his child gets kidnapped.

Jolson makes it clear: unless Mark does what he orders him to do, the boy dies. Using the helpless man in his plan to bring down other criminal organizations of the city, Jolson sends Mark on suicidal missions during which Mark has three terrible choices: walk away and lose his son, get killed in a battle against overwhelming odds, or single-handedly help Jolson to get rid of his adversaries.

Once the player completes Mark Hammond's story, a new scenario opens, in which the player controls Frank Carter, a vigilante cop who won't stop until he brings Charlie Jolson to justice. Frank's scenario is parallel to Mark's, shedding more light on events that remain somewhat unexplained during Mark's scenario.

The Getaway is a hybrid of driving and third-person shooter gameplay, similar in concept to Grand Theft Auto III. London has been digitally recreated for this game, and the player can explore it freely on foot or driving a vehicle. Unlike GTA III, missions follow each other linearly, dictated by the plot. The game is more story-driven and does not have any free-roaming activities. Many of the driving sequences also have a time limit, restricting free exploration.

Each mission usually consists of a driving section, which requires the player to drive to a certain destination (sometimes chasing another vehicle or being chased by enemies), and a third-person shooter section, often with an additional driving section afterwards. Police or rival gangs will frequently pursue the protagonist. The player can hijack any car or bus from the streets, or move on foot.

Third-person shooter sequences are longer and more prominently featured than the corresponding sections of GTA III. The protagonist can perform a variety of moves: sneak, crouch, roll to the sides, etc. A few missions are completely stealth-oriented, and are failed if the player character is discovered by enemies. It is possible to use the butt of the gun as a melee weapon, and also take hostages to prevent the police from shooting at the player character.

The game's distinguishing visual feature is a total absence of visible interface and text feedback. Rather than consulting a map, the player follows the car's blinking lights to arrive at the right destination. Damage taken by the protagonist is indicated by the character bending over, walking slower, and having blood on his clothes. Health is recovered by resting (leaning against a wall); there are no health kits scattered around. The protagonist can carry only two small or one larger weapon at once.