and what is his role?
He transforms into the Ant-Man.
Scott Lang (Marvel Cinematic Universe)
Scott Lang is a character portrayed by Paul Rudd in the Marvel Cinematic Universe (MCU) film franchise, based on the Marvel Comics character of the same name and known commonly by his alter ego, Ant-Man. 
where does the movie ant man take place Treasure Island, San Francisco. who directed it? Edgar Wright. who is the protagonist of this film? Scott Lang.
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Scott Lang (Marvel Cinematic Universe) [SEP] Introduction
Scott Lang is a character portrayed by Paul Rudd in the Marvel Cinematic Universe (MCU) film franchise, based on the Marvel Comics character of the same name and known commonly by his alter ego, Ant-Man. , the character is a prominent figure of the MCU, having appeared in four films from his introduction in "Ant-Man" up to "", with references to the character or snippets of archival footage appearing in several other films. Lang will also appear in the upcoming Disney+ animated series "Marvel's What If...?".