Strike Back is a British action thriller television series based on the 2007 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 Secret Intelligence Service (SIS, aka MI6), who operate several high risk, priority missions around the world. The six-part first series began broadcasting on Sky One on 5 May 2010.

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, Strike Back: Shadow Warfare, which was broadcast on Cinemax beginning 9 August 2013. A ten-episode, fifth series titled Strike Back: Legacy aired in 2015, with the last episode airing on 29 July, and at that point, this was to be final series for the show.

On 8 December 2016, Cinemax and Sky announced they would revive the show for a sixth series, Strike Back: Retribution which debuted on 31 October 2017 on Sky One in the UK, and in the US on Cinemax on 2 February 2018. On 27 March 2018, Strike Back was renewed for a seventh series titled Strike Back: Revolution. Filming commenced in late 2018, with a release date of 25 January 2019 on Cinemax and 28 February 2019 on Sky One. On 27 February 2019, Cinemax renewed the series for an eighth and final series titled Strike Back: Vendetta, which premiered on 14 February 2020.

Ratings for Strike Back were relatively high for the original networks. The Sky One premiere was viewed by almost 400,000 viewers (according to overnight figures), tripling the average audience share for the channel's time slot after three months. Project Dawn premiered to more than 600,000. The Cinemax premiere saw the network's best ratings since 2005.

Episodes

Chris Ryan's Strike Back (2010)

John Porter (Richard Armitage) led an SAS rescue mission in Iraq, on the eve of the invasion in 2003. During the operation, Porter spared the life of a thirteen-year-old suicide bomber. Shortly after, the boy apparently killed two of Porter's team. Porter was held responsible by his commanders and forced to resign.

Seven years later, Porter is "reactivated" following the kidnap of journalist Katie Dartmouth (Orla Brady), daughter of a former government minister, by the same terrorists whom he had fought in 2003, including the same boy, As'ad. Porter succeeds in rescuing Dartmouth and joins Section 20, headed by Hugh Collinson (Andrew Lincoln), who had also taken part in the fateful mission. By the end of the series, it is revealed that Collinson was the one who killed the two soldiers, and covered this up. Section 20 officer Layla Thompson (Jodhi May) discovers his guilt, and blackmails Collinson into saving Porter's life in Afghanistan. There, Porter learns that during the mission, Collinson panicked and mistook the soldiers for terrorists. Taliban members raid their location, and Collinson is mortally wounded while aiding Porter's escape.

Project Dawn (2011)

Porter is captured by a Pakistani terrorist called Latif (Jimi Mistry) while investigating Project Dawn, one of Latif's planned operations. Sergeant Michael Stonebridge (Philip Winchester) finds Damian Scott (Sullivan Stapleton), a disgraced ex-Delta Force operative who cannot even find work with private military contractors. Scott had previously worked with Porter to track Latif. After Porter is executed, Section 20 discover that Porter left the team clues to a hotel in New Delhi, India, where a group of terrorists attempt to capture a weapons scientist with knowledge of hidden weapons of mass destruction originally used to plant in Iraq, which serves as a part of Project Dawn. The weapon, namely VX nerve gas, was kept in storage, and Latif knew of its existence.

Section 20's worldwide search for Latif ends in Budapest, Hungary, where they learn he is implanting explosives inside suicide bombers' bodies, which in turn will release the VX. The attempted attacks against a World Summit were actually a diversion to capture former Pakistani general Akmal Ramiz (Silas Carson), who Latif fears will make Pakistan more accessible to the west. He also captures Section 20 head Colonel Eleanor Grant (Amanda Mealing) in an attempt to confess to "Operation Trojan Horse", which planned to plant VX in Iraq, while also exposing Porter and framing Scott; Grant attempted to cover up the operation in shame. In the end, Grant forces Latif to shoot an empty VX canister, with the explosives still intact, killing them both. Although Scott gains the file that would clear his name, he decides to burn the file and remain in Section 20. Meanwhile, Stonebridge leaves the organisation to be with his pregnant wife.

Vengeance (2012)

Former military intelligence operative Major Rachel Dalton (Rhona Mitra) takes charge of Section 20. Its operatives work throughout Africa to recover four nuclear triggers which have fallen into the wrong hands after a mission in Somalia. The triggers were originally sold to Conrad Knox (Charles Dance), an English billionaire and philanthropist based in South Africa, who runs the Knox Foundation. The Foundation has been set up with the aim of disarming unstable regions, but it becomes apparent that Knox is arming his own militia with the weapons and is building nuclear weapons containing the triggers. He intends to liberate Africa "to a point where its voice is not just heard but listened to." Owing to Knox's influence, Section 20 is forced to go dark to stop him.

In the meantime, Stonebridge seeks revenge on Craig Hanson (Shane Taylor) for murdering his wife and returns to Section 20, while Scott has to contend with Central Intelligence Agency (CIA) agent Christy Bryant (Stephanie Vogt), with whom he used to carry out contract killings. Scott also has a relationship with Rebecca, a Mossad contract assassin (Lyne Renée). By the conclusion of the series, two of the bombs are recovered, and the remaining two are disarmed before they can destroy Johannesburg. Stonebridge fulfills his revenge and Knox, fleeing the failed attempt, dies by accidentally shooting himself in a street altercation with the very South Africans he hoped to empower.

Shadow Warfare (2013)

Scott and Stonebridge are recalled from holiday in California to capture Leo Kamali (Zubin Varla), a high-ranking member of a terrorist cell led by al-Zuhari, an elusive terrorist. After capturing him in Colombia, it is revealed that Kamali is working deep cover with the CIA to stop al-Zuhari. As Kamali is pressured to work with Section 20, Dalton is suspended by Lt. Colonel Philip Locke (Robson Green), who takes charge. Dalton is later killed by the Real Irish Republican Army (IRA), who have joined forces with al-Zuhari's group. In the meantime, Scott and Stonebridge are wanted by the Russian mafia after killing the son of mob boss Arkady Ulyanov (Marcel Iureș) in Colombia. Scott learns he fathered a child from one of his past relationships, while Stonebridge is infected with a neurotoxin during one of Section 20's missions in Beirut, which affects his combat abilities.

After attacking the British Embassy in Budapest, the IRA and al-Zuhari's group steal a NATO hard drive and send it to a prison in Russia where a Swedish hacker and prisoner, Erik Andersson, is forced to decrypt it. While on mission in Russia, Section 20 also become aware of a secretive facility where al-Zuhari's scientists are weaponising smallpox to be used to attack NATO bases. After the mission, Stonebridge is given the antidote to the toxin, and Kamali is executed by al-Zuhari's men for being a double agent. Section 20 learn that al-Zuhari's group intends to attack a NATO base in Berlin, Germany, where it is revealed that Kamali faked his death, having been behind the operation the entire time (it is revealed that the Israelis killed al-Zuhari six months before). After the terrorists successfully infect a train and the NATO base's hospital, Section 20 thwart Kamali's plot to fly a plane over Berlin to infect the city. Both Kamali and Ulyanov are killed by 20 during an exchange arranged by Locke. In his last moments, Kamali reveals that his daughter Ester has a pendant that contains the cure to the smallpox, though only enough to save those infected at the hospital.

Legacy (2015)

Strike Back returned to Cinemax on 31 July 2015 for the final series of ten new episodes. Initially scheduled for summer 2014, the series had to be pushed back owing to an off-set injury to series star Sullivan Stapleton.

Scott and Stonebridge are sent on a mission to rescue Chloe Foster, the kidnapped daughter of Robin Foster, a British diplomat negotiating North Korea's nuclear disarmament. Robin is forced to carry a bomb into the chambers of the North Korean delegation, killing a general. Section 20 investigates Office 39, a clandestine branch of the North Korean army, and identifies Robin's wife, Mei Foster, as an Office 39 deep-cover agent. Mei has spent her life trying to advance North Korea's nuclear programme and has used her position to broker a deal with the yakuza to acquire key components for long-range missiles. Section 20 are unsuccessful in intercepting a shipment of vanadium, leading Scott and Stonebridge to infiltrate North Korea and sabotage their missile production, setting the programme back decades. Mei is blamed for the failure—despite repeatedly warning her government about Section 20—and turns rogue, activating a network of sleeper agents across Europe. They build an improvised nuclear device and plan to set it off at a summit in Geneva. Section 20 operatives disarm the bomb but the diplomatic fallout sees Whitehall disavow them. Scott and Stonebridge are ambushed by a CIA kill team and go on the run.

Retribution (2017)