A spy organisation recruits a promising street kid into the agency's training program, while a global threat emerges from a twisted tech genius.
Agent Harry "Galahad" Hart (Colin Firth) from the Kingsman Secret Service helps troublemaker Gary "Eggsy" Unwin (Taron Egerton), who is the son of an Agent that saved the lives of Harry and his team, sacrificing himself seventeen years ago.
Harry invites Eggsy to be a candidate to the vacancy of a new Agent in the agency, and he is trained by Agent Merlin (Mark Strong) and competes with other candidates.
Meanwhile, the Kingsmen investigate the industrialist Valentine (Samuel L. Jackson), an insane genius of technology who is plotting a deadly plan with his assistant Gazelle (Sofia Boutella) to save the Earth from global warming, eliminating most of the population with a chip and saving only those that he has chosen.