One major plot hole in Iron Man 2 shows its ugly head when Whiplash attacks Tony Stark on the racetrack in Monaco. Prior to these events, Tony Stark is still laying the groundwork for being Iron Man. He starts the year-long Stark Expo, creates new suits, and deals with the toxic effects the Palladium from the original arc reactor had on his body, slowly killing him. Iron Man's constant checking of his blood toxicity levels affects his character for the first half of the movie, approaching life as someone with limited time. Iron Man is also called to testify in front of the U.S. Senate regarding his use of the armor, which he describes not as a weapon, but as part of him.
Throughout Iron Man 2, Stark is finding ways to remain a superhero at any cost. He is erratic, unreliable, and goes off the rails before Nick Fury and Black Widow show up with a supplement that helps save his life. He dons the Iron Man armor at his birthday party only to blow up liquor bottles, and eventually, a watermelon, putting everyone present in danger.
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His risky behavior as Iron Man could have cost some people their lives. This is shown when he decides to get into the seat of a racecar and participate in the race in Monaco. It is at this point that Whiplash finally appears, with his super-powered whips in tow, to ostensibly whip Tony's car in half, killing him in the process. As Iron Man 2's villain Whiplash walks fearlessly across the raceway, he powers up his suit, and his clothes burn off, leaving him exposed to the elements from the waist up. It's a very cool, cinematic choice by director Jon Favreau to introduce the villain this way, but it does introduce a plot hole,
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