Iron Man 2 picks up where the first film left off, with Tony Stark facing new challenges in his dual role as the CEO of Stark Industries and as Iron Man. He is hailed as a hero for his actions in the first film, but he also faces scrutiny for his secret identity and his refusal to share his technology with the military.
As Stark's health deteriorates due to the arc reactor in his chest, he becomes increasingly reckless, leading many to question his fitness to be a hero. Meanwhile, a new villain arises in the form of Ivan Vanko, a Russian physicist who has developed his own version of Stark's technology and seeks revenge for his father, who was ostracized by Stark's father.
Stark also faces pressure from competing interests, including rival industrialist Justin Hammer, who enlists Vanko to create a new generation of armored suits. Meanwhile, the U.S. government, represented by Senator Stern and Colonel James Rhodes, seeks to take control of Stark's technology and use it for their own purposes.
Despite these challenges, Stark continues to refine and improve his Iron Man suits, with the help of his trusted friend and assistant Pepper Potts. He also enlists Rhodes, who becomes War Machine, to fight alongside him in his battles against Vanko and Hammer.
In the climax of the film, Stark teams up with Rhodes and Potts to take down Vanko and his army of armored drones in a spectacular showdown at the Stark Expo. Along the way, he also learns to be more responsible with his power, both as a hero and as a inventor, setting the stage for the future of the Marvel Cinematic Universe.