Strike Back is a British/American action and military television series, based on a novel of the same name by novelist and former Special Air Service soldier Chris Ryan. The series follows the actions of Section 20, a secretive branch of the British Defence Intelligence service, who operate several high risk, priority missions throughout the globe. The series began broadcasting on Sky1 on 5 May 2010, showing the first six-part series. After a second series was commissioned, it was announced that Cinemax would co-produce the franchise. The first episode of the ten-part second series, under the banner title Project Dawn in the United Kingdom, first aired on Cinemax on 12 August 2011. The ten-part third series, under the title Strike Back: Vengeance, began airing on Cinemax on 17 August 2012. On 3 October 2012, Cinemax and Sky commissioned a fourth series, which was broadcast on Cinemax beginning 9 August 2013. A ten-episode fifth and final season aired in 2015.

The following is a list of characters that have appeared on the television series.

Section 20 CharacterActorSeries appearances John Porter Richard Armitage 1–2John Porter is the main protagonist of the first series who is a Sergeant in the British SAS. In 2003 he took part in a botched operation to rescue Kenneth Bratton, a weapons contractor held hostage in Iraq on the eve of the American-led invasion, where two soldiers were killed and a third left in a persistent vegetative state. Porter was blamed as they suspected the killer was a 13-year-old hostile, As'ad, and Porter failed to kill him. As a result, he resigned a disgraced operator, he could not find suitable employment, and became estranged from his wife and daughter. Seven years later, he is drafted back into service to work for Section 20. He ultimately learns that the boy, was not the killer, but his new superior Hugh Collinson.

In the second series, Project Dawn, Porter worked to capture terrorist Latif in Pakistan, who is planning the eponymous operation. Instead, Porter gets captured, and later executed. It is later revealed that Porter was exposed by Pakistani intelligence and to a lesser extent, Eleanor Grant, Collinson's successor.

Armitage dropped out of the role after the first series to play Thorin Oakenshield in The Hobbit film trilogy.

First appearance: Series 1, Episode 1 Last appearance: Project Dawn, Episode 1 Hugh Collinson Andrew Lincoln 1Major Hugh Collinson is the head of Section 20 in the first series. Collinson was a military intelligence officer who worked with Porter in the SAS mission to rescue Kenneth Bratton. When enemy re-enforcements arrived Collinson accidentally killed two SAS soldiers. However, Porter was given the blame. Later, Collinson is promoted to lead Section 20. In 2010, journalist Katie Dartmouth is kidnapped by terrorists in Iraq, among them is As'ad, who is the only witness to Collinson's shooting. Collinson covers his tracks by refusing to aid As'ad, likely leading to his death. The truth is later discovered by Layla, after the third soldier dies after seven-years in a coma, and ballistics evidence matches Collinson's gun. Collinson is later forced to help Porter in Afghanistan, after he sells the latter out by the American government to kill him. Collinson is shot several times by the Taliban while helping Porter escape, and in his dying moments uses a grenade to kill them.

First appearance: Series 1, Episode 1 Last appearance: Series 1, Episode 6 Danni Prendiville Shelley Conn 1Danni Prendiville is an officer in Section 20. In the first series, Prendiville oversees Porter's training after he joins the unit, and then has sex with him. The two later have an affair. Her status since the end of the first series is unknown.

First appearance: Series 1, Episode 1 Last appearance: Series 1, Episode 6 Layla Thompson Jodhi May 1Layla Thompson is a Lieutenant in military intelligence and works alongside Collinson in Section 20. Throughout the first series her demeanor towards Porter's employment in the section changes. At first she comes to resent Porter, but as time goes by an opens up to him. She later becomes aware of the truth behind the botched 2003 operation and ultimately learns it was Collinson who killed the soldiers. She then confronts Collinson and blackmails him into aiding Porter in Afghanistan or she will report her findings to Collinson's superiors. Her status since the end of the first series is unknown.

First appearance: Series 1, Episode 1 Last appearance: Series 1, Episode 6 Michael Stonebridge Philip Winchester 2–6Colour Sergeant Michael Stonebridge is one of the two series protagonists, alongside Damien Scott, from Project Dawn to Legacy. In the series, Stonebridge is a Royal Marine Commando turned SBS operator working for Section 20, and is married to his wife Kerry. Despite this, Stonebridge has an affair with Section 20 officer Kate Marshall. In Project Dawn, Stonebridge is assigned to collect Damien Scott to identify Latif, a mysterious terrorist. Their working relationship begins somewhat rocky due to the duo's polarising views on tactics. He ends his affair with Kate, but soon afterwards, Kate is killed in a bomb, and Stonebridge temporarily loses focus on his job. When Kerry announces she is pregnant, the wife pressures Stonebridge to leave Section 20. After foiling Latif's Project Dawn, Stonebridge decides to resign.

In Vengeance, Stonebridge trains British special operation recruits, but during a live-ammunition training exercise, he is forced to kill a recruit when he breaks down and threatens the other recruits. He briefly rejoins Section 20 to rescue Scott in Somalia, but then rejoins full-time after the dead recruit's brother, Craig Hanson, avenges his death by killing Kerry. Stonebridge becomes fixated on killing Hanson, who is now working for Conrad Knox, the season's antagonist, and hence loses focus again. By the end of the series, Stonebridge fulfils his revenge, but decides to forgive Hanson also.

In Shadow Warfare, he and Scott are ordered to capture Kamali, a lieutenant of elusive terrorist al-Zuhari, in Colombia, and kill Viktor Ulyanov of the Russian mafia in the process. This action results in a hit his and Scott's life as his father Arkady is a high-ranking mob boss. In the third episode, Stonebridge is unknowingly contaminated with a chemical weapon leaked from outdated missiles in a warehouse. As a result, he suffers episodes of impaired visions, affecting his combat abilities. He is not made aware of his condition until episode seven, where he has only days to live. He is later given the antidote and manages to survive to fight again, while also having the bounty lifted when Arkady is killed.

During the events of Legacy, Stonebridge begins to seriously contemplate his life when he is forced to confront the idea that his government would consent to having him killed if it would fulfil a political end. He expresses the hope that he will die as a soldier because he has always been a soldier and has no identity outside it. After surviving pursuit by a CIA assassination squad, Stonebridge is officially the only survivor of Section 20. He faces an uncertain future as he tries to adjust to civilian life, but chooses to join Scott and his son on a road trip to Las Vegas.

Stonebridge makes a guest appearance in Retribution, partnering with Scott to aid the reformed Section 20. Since the events of Legacy they have become "independent contractors" carrying out sensitive and dangerous intelligence operations on behalf of the British government, giving Whitehall plausible deniability.

First appearance: Project Dawn, Episode 1 Last appearance: Retribution, Episode 10 Damien Scott Sullivan Stapleton 2–6First Sergeant Damien Scott is one of the two series protagonists, alongside Michael Stonebridge, from Project Dawn to Legacy. Scott was a member of the US Army Rangers before joining Delta Force working to investigate possible weapons of mass destruction in Iraq. When he began questioning mysterious WMD intelligence, he found himself dishonorably discharged when two pounds of opium were planted in his possession. He was considered so unorthodox in his methods, that even private military companies would not hire him. He is first seen in Malaysia entering fighting contests for income. He is brought in by Section 20 to identify Latif, though Scott later admits he never actually saw him. Scott later becomes a member of Section 20. Throughout the series he realises that he was set up by Eleanor Grant as part of a mission to plant weapons in Iraq. He acquires the file that would exonerate him, but he decides to burn the file instead.

In Vengeance Scott is captured while on a rescue mission in Somalia, but later rescued by Stonebridge. While working to recover four stolen nuclear triggers, he is reacquainted with Christy Bryant. It is revealed that after his dishonourable discharge, he and Christy worked together to kill numerous targets around the world that posed a threat to the United States, but stopped in 2005 when he killed the son of a target in a car bomb in Ecuador. By the end of the series, Scott reluctantly partners up with her once more to stop Conrad Knox from selling and detonating four nuclear weapons.

In Shadow Warfare he and Stonebridge are wanted by the Russian mafia for killing the son of mob boss Arkady Ulyanov during a mission to capture Kamali. Over the course of the series, Scott learns that he fathered a son, Finn, from one of his past relationships while in the States. He acquires a bag of diamonds from one of the missions, and decides to give it to his son's mother Rebecca. By the end of the series, Scott begins a relationship with Julia Richmond.

In Legacy, Finn finds himself in trouble at home and runs to Bangkok to meet his father. Initially believing Scott to be an IT consultant, the two are attacked by the Yakuza and Scott finds himself acting as a father for the first time. When he and Stonebridge infiltrate North Korea, Scott surrenders upon learning that the North Koreans have abducted Finn and even confesses to committing an act of war to protect him. Once the three escape North Korea, Scott begins contemplating life after Section 20 having previously admitted that he expects to die in action. When he and Stonebridge evade a CIA-sanctioned hit squad, Scott stages his own death, allowing him to return to the United States and be a father to Finn.

Scott makes a guest appearance in Retribution, partnering with Stonebridge to aid the reformed Section 20. Since the events of Legacy they have become "independent contractors" carrying out sensitive and dangerous intelligence operations on behalf of the British government, giving Whitehall plausible deniability.

First appearance: Project Dawn, Episode 1 Last appearance: Retribution, Episode 10 Eleanor Grant Amanda Mealing 2Colonel Eleanor Grant is the head of Section 20 following the demise of Hugh Collinson, in Project Dawn. Her main assignment was to stop Latif, who killed Porter. She reluctantly takes in Scott as an operative. By the end of the series, it is revealed that she took part in "Operation Trojan Horse", a project to plant VX nerve gas in Iraq to prove the existence of weapons of mass destruction there. Though the operation was abandoned, she was ashamed of her actions (having indirectly caused the events of Project Dawn), and in her attempt to cover up her involvement, she framed Scott's possession charges and indirectly exposed Porter leading to his death. In the climax, Grant forces Latif to shoot an explosive canister under her jacket, killing Latif and herself. In Vengeance she would be replaced by Rachel Dalton as head of the section.

First appearance: Project Dawn, Episode 1