The Secret Service is about a boy named Eggsy. He lost his dad when he was small. Later, he meets Harry Hart, who helps Eggsy join a secret group called Kingsman. Eggsy trains to become a secret agent. The training is hard, but Eggsy is brave and does well. At the same time, a bad guy called Valentine makes a dangerous plan. Valentine wants to control people using phones with special SIM cards. These cards make people violent and dangerous. Eggsy and the Kingsman group must stop Valentine. In the end, Eggsy fights Valentine and wins. He saves the world and becomes a real Kingsman agent. Eggsy feels proud because he did something important, just like his father.