Iron Man 3 opens with a flashback to 1999, narrated by Tony Stark. It’s the eve of the new millennium, and Tony is partying with an attractive scientist who is interested in DNA modification as it relates to regeneration. They have an elevator encounter with an enthusiastic scientist interested in recruiting Tony (and the woman) to his new company. We’re told via Tony’s voice over that this is where it all started.
We then jump to modern day Tony Stark, struggling to deal with recent events. Christmas is approaching, and Tony has been spending all of his time in the lab, hardly ever sleeping, working on perfecting a new suit of Iron Man armor that will fly to his body in pieces at just a thought. He’s currently living with Pepper Potts, who is still running his company. Tony hasn’t been sleeping because he’s still haunted by his near-suicide in the wormhole in New York during the events of The Avengers.