Kingsman: The Secret Service (2014)

During a mission in the Middle East in 1997, probationary secret agent Lee Unwin sacrifices himself to protect his superior, Harry Hart, from an explosion. Hart, blaming himself for Lee's death, returns to London to give Lee's widow, Michelle, and her young son Gary "Eggsy" a medal engraved with an emergency assistance number and tells him of a special phrase. Seventeen years later, Eggsy is a stereotypical chav, having dropped out of training for the Royal Marines despite his intelligence and talents for both gymnastics and parkour. After getting arrested for stealing a car from his gangster stepfather, Dean, and crashing it, Eggsy calls the number and recites the phrase, "oxfords not brogues". Hart arranges his release and explains that he is a member of Kingsman, a private intelligence service founded by British elite who lost their heirs in World War I and put their money towards protecting the world; the organisation is named for the tailor shop that clothed them in Savile Row, which they now use as a front for their bases. Hart, code name "Galahad", explains a position is available, as agent "Lancelot" was killed by the assassin Gazelle while trying to rescue university professor James Arnold from kidnappers. Eggsy becomes Hart's candidate.

Kingsman's technical support operative "Merlin" discovers that Professor Arnold is working as though nothing has happened. Hart attempts to interrogate him at Imperial College London, but a microchip in Professor Arnold's neck explodes, killing him. The detonation signal is traced to a facility owned by Gazelle's employer Richmond Valentine, an Internet billionaire and philanthropist who has offered everyone in the world SIM cards that grant free cellular and Internet connectivity. Hart, posing as a billionaire philanthropist, meets Valentine face to face. Other candidates are eliminated through various dangerous training tests run by Merlin, until only Eggsy and Roxy, a candidate Eggsy befriended, are left. Eggsy refuses to complete the final test—shooting a Pug puppy he raised during the training process, and Roxy is named the new "Lancelot". As he is kicked out, Eggsy returns home by a designated taxi. Upon return, he discards his suit to the ground and tries to resolve unfinished business, attempting to get back at Dean. Outside the pub, Dean and his gang are seated on benches. Eggsy threatens to pick a fight with Dean but the taxi's window automatically rolls up and drives Eggsy back to Hart. Eggsy complains and expresses his distaste that he must "shoot a dog to get the job" but Hart reveals his taxidermied dog that he kept as part of his training, stating that the gun had held a blank. After a brief argument, Hart reminds Eggsy that everything he has done so far was to repay Eggsy's father for his service and re-recruits him back into Kingsman.

Hart learns of Valentine's connection to an obscure hate group's church in Kentucky, and travels there, wearing glasses containing a video transceiver. As Eggsy watches live footage on a laptop, Valentine activates the SIM cards in the church, triggering a signal that causes the parishioners and Hart himself to become murderously violent. Hart's spy training leaves him as the only survivor. Outside the church Valentine explains what happened before shooting Hart in the face. Eggsy is in shock but returns to Kingsman headquarters. He notices that Chester "Arthur" King, Kingsman's leader, has a scar on his neck just like Professor Arnold's. King reveals that Valentine plans to transmit his "neurological wave" worldwide via satellite network, believing the resulting "culling" of most of the human race will avert its extinction via global warming. Only those Valentine has chosen will be unaffected and invites Eggsy to be a part of "a new world". Eggsy declines this offer and stays loyal to Hart. King attempts to kill Eggsy with a poisoned drink, but Eggsy distracts King and switches glasses with him and King ends up poisoning himself. Eggsy uses the nib of his custom Kingsman fountain pen to cut open King's scar, retrieving the chip installed.

Eggsy, Merlin and Roxy set out to stop Valentine. Roxy uses high-altitude balloons to destroy one of Valentine's satellites and break up the network, but Valentine secures a replacement. Merlin flies Eggsy to Valentine's base, where he masquerades as King. Eggsy is discovered by a failed Kingsman recruit, Charlie Hesketh, leading to both Eggsy and Merlin being cornered. On Eggsy's suggestion, Merlin activates the implanted chips' failsafe, killing almost everyone installed with a chip. Their heads explode and Eggsy is able to escape the guards that previously cornered him. Valentine activates the signal using his hand, triggering worldwide pandemonium. Eggsy cuts Gazelle's arm mid-air with his oxford shoe, tipped with lethal neurotoxins. Upon landing, the toxin spreads and kills her. He then uses one of her sharpened prosthetic legs to impale Valentine, throwing it from below and killing him, stopping the signal and ending the threat. Afterwards, he grabs champagne and two glasses, sharing a sexual encounter with Tilde, Crown Princess of Scandinavia, whom Valentine had previously abducted. In a mid-credits scene, Eggsy, now the new "Galahad", offers his mother and half-sister a new home away from his abusive stepfather, who he knocks unconscious in the same way that Harry earlier knocked out a gangster.