I took stuff, how does that make you feel? Does it make you feel bad? Good, BECAUSE THAT'S HOW I FEEL!!
~ Justin Hammer to Ivan Vanko
What I saw you did to Tony Stark on that track, how you stepped up to him in front of God and everybody, that was... WOW!
~ Justin Hammer explains how he was impressed by Vanko's intimidation and destruction at Monaco

Justin Hammer is the secondary antagonist of the 2010 Marvel film, Iron Man 2. He is an arms dealer, Tony Stark/Iron Man's business rival and the owner of "Hammer Tech"

He was portrayed by Sam Rockwell who also portrayed Eric Knox and William Wharton.

Iron Man 2

In that version, Justin Hammer was portrayed a little different compared to the comic book version: Justin appeared to be younger than Tony Stark instead of being older, he whined when he didn't get his way, and appeared to be less intelligent. Hammer was one of Tony's rivals. He owned Hammer Tech; a company that made weapons. Hammer had been trying to create an exact replica of the Iron Man Armor, but in the process, injured just about everyone who tried the suit. After he witnessed Iron Man fight Whiplash, Hammer was impressed with Whiplash and planned to break him out of prison, while at the same time place a fake Whiplash to take his place so that they could perform a fake death. Hammer and Whiplash made a deal with each other that if Ivan made a huge amount of Iron Man Armor, they would put an end to Tony's career. What Hammer didn't know was that Whiplash was planning to turn against him and destroy Tony with the same armor. When Pepper Potts, Tony's girlfriend and temporary CEO of Stark Industries found out that Hammer was working with Vanko, she called the cops on him. Some time later, S.H.I.E.L.D. found out that Hammer had helped Whiplash escape, they arrested him for helping a prisoner escape. He then vowed revenge on Tony and Pepper for this.

All Hail The King

In the Marvel short: All Hail the King, Justin Hammer was a prisoner who was seen in the end credits with other prisoners, including the Iron Man villain, The Mandarin. Watching Trevor Slattery (The actor who had been hired to impersonate the Mandarin) in the prison cafeteria being admired and fawned over by other inmates, Hammer remarks that he doesn't understand Slattery's appeal and isn't impressed with him at all.

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