G8 intelligence services locate Pakistani arms trafficker and terrorist mastermind Aamir Barkawi (Alon Moni Aboutboul) at his compound on the outskirts of Lahore, and authorize a US Air Force drone strike during his daughter's wedding, killing Barkawi's family and seemingly Barkawi himself.
Two years later, British Prime Minister James Wilson suddenly dies, and the G7 prepare to attend his funeral in London. Secret Service Director Lynne Jacobs (Angela Bassett) assigns agent Mike Banning (Gerard Butler) to lead American President Benjamin Asher's (Aaron Eckhart) overseas security detail, even though Banning's wife Leah (Radha Mitchell) is due to give birth in a few weeks. The entourage arrives via Air Force One at Stansted Airport, and Banning arranges an earlier arrival at Somerset House in London via Marine One.
As Asher's Presidential State Car arrives at St Paul's Cathedral, a group of mercenaries led by Barkawi's son Kamran (Waleed Zuaiter) launch coordinated attacks on the city disguised as Metropolitan Police, the Queen's Guardsmen, and other first responders, killing five Western leaders, damaging major landmarks and generating mass panic. Asher's early arrival throws off the St. Paul's attack, and Banning returns him and Jacobs to Marine One. The terrorists destroy the helicopter's escorts with Stinger missiles, forcing the damaged helicopter to crash-land in Hyde Park. Fatally injured, Jacobs makes Banning promise to stay alive for his unborn child, and to punish those responsible for the attack. Banning escorts Asher into the London Underground as the city's power is lost and residents shelter indoors.
In Washington, D.C., American Vice President Allan Trumbull (Morgan Freeman) investigates the incident with British authorities while trying to track down the President. He receives a call from Barkawi, still alive after all and operating in Sanaa. Seeking revenge for the drone strike that killed his daughter, and having poisoned Wilson to lure the G7 to London, Barkawi knows Asher is still alive, and promises that if Kamran captures him, he will broadcast Asher's execution online. Trumbull orders his staff to locate Barkawi's known operatives and find any connection to the attack, while British authorities stand down all first responders so any left in the open can be identified as terrorists.
After leaving a sign to be picked up by satellite, Banning leads Asher to an MI6 safe-house, where agent Jacquelin "Jax" Marshall (Charlotte Riley) briefs them. Marshall receives a voice message from Trumbull that they saw Banning's sign and an extraction team is en route. Security monitors display an approaching Delta Force team, but Banning realizes they have arrived too soon and are actually Barkawi mercenaries. He fights and kills all of them and drives away with Asher, but their car is struck before they can reach the US Embassy, and Asher is taken. Banning is rescued by the combined Delta/SAS extraction team, who suspect a mole in the British government.
Trumbull's staff identify a building owned by one of Barkawi's front companies, drawing massive power despite being unoccupied, and realize it is Kamran's headquarters. Banning joins the extraction team to infiltrate the building, arriving seconds before Kamran can decapitate Asher. Kamran escapes when his hacker Sultan Mansoor (Mehdi Dehbi) drops a grenade with his dying breath, forcing Banning to protect Asher from the blast. Banning and Asher escape just before the building is destroyed by the Delta Force/SAS squad, killing Kamran and the remaining terrorists. Marshall and British authorities restore London's security system and, discovering that MI5 Intelligence Chief John Lancaster (Patrick Kennedy) was Barkawi's mole, Marshall kills him when he resists arrest. Trumbull tells Barkawi that his plan failed, moments before US federal authorities attack the building armed with another drone strike, killing Barkawi and the remaining members of his terrorist group.
Two weeks later, Banning is home spending time with Leah and their newborn child Lynne, named after Jacobs. As Banning contemplates sending a letter of resignation, he watches Trumbull speak on television regarding the recent events, with a message that the U.S. will prevail. Inspired, Banning deletes the letter.
Gerard Butler as Secret Service Agent Mike Banning
Aaron Eckhart as President Benjamin Asher
Morgan Freeman as Vice President Allan Trumbull
Alon Moni Aboutboul as Aamir Barkawi
Angela Bassett as Secret Service Director Lynne Jacobs
Robert Forster as US Army General Edward Clegg
Jackie Earle Haley as White House Deputy Chief of Staff DC Mason
Melissa Leo as Secretary of Defense Ruth McMillan
Radha Mitchell as Leah Banning
Sean O'Bryan as NSA Deputy Director Ray Monroe
Charlotte Riley as MI6 Agent Jacquelin "Jax" Marshall
Waleed Zuaiter as Kamran Barkawi
Colin Salmon as Commissioner Sir Kevin Hazard
Bryan Larkin as SAS Captain Will Davies
Patrick Kennedy as MI5 Counter-Intelligence Chief John Lancaster
Mehdi Dehbi as Sultan Mansoor
Adel Bencherif as Raza Mansoor
Michael Wildman as Secret Service Agent Voight
Andrew Pleavin as Secret Service Agent Bronson
Deborah Grant as Doris
Clarkson Guy Williams as British Prime Minister Leighton Clarkson
Penny Downie as Home Secretary Rose Kenter
Philip Delancy as French President Jacques Mainard
Alex Giannini as Italian Prime Minister Antonio Gusto.
Elsa Mollien as Mrs Viviana Gusto
Nancy Baldwin as German Chancellor Agnes Bruckner
Nigel Whitmey as Canadian Prime Minister Robert Bowman
Julia Montgomery Brown as Mrs Bowman
Tsuwayuki Saotome as Japanese Prime Minister Tsutomu Nakushima
Lawrence O'Donnell as himself (uncredited)
sequel to Antoine Fuqua's 2013 film Olympus Has Fallen