The main character of the film is Steve Rogers (Chris Evans), a young guy from Brooklyn, a true warrior in character, but too frail and sickly for military service. Forty years, the Second World War is in full swing. It's hard for Steve to stay away, looking at how all his comrades go to the front. He is a patriot and is ready to give his life, defending his own, but because of poor health he is considered unfit for military service. Rogers shares his experiences with his friend, Sergeant James Barnes. Dr. Abraham Erskine, a Bavarian scientist working for the US government, becomes a casual witness to their conversation and makes Steve an unexpected proposal. The fact is that the country is recruiting for an experimental course of military training, the purpose of which is to create a super-soldier. It seems that the weak Rogers is completely inappropriate for this role, but Dr. Erskin convinces the young man that the main criterion for the selection of candidates is not the physical data, but the moral qualities of future soldiers. Steve agrees to participate and ends up in a military camp led by Colonel Phillips and charming officer Carter. Together with other recruits, the main character of the fantastic blockbuster "The First Avenger" passes the course and becomes the main candidate for the use of experimental serum. After the injection, he is exposed to the influence of vita-rays and turns into a powerful warrior with superhuman strength. However, the developers of the experiment did not have time to rejoice in success, since immediately after the transformation of Steve, the laboratory was blown up, and Erskine was killed by a traitor who was squandering into the team. Now on the streets of the city is declared a lone warrior "Captain America", ready to fight for justice. His first task will be the discovery and complete destruction of the members of the terrorist organization HYDRA, which is preparing to gain world power with the help of the latest weapons.