Fan Casting Dr. Bruce Banner in George Nolfi's Captain America

Dr. Bruce Banner was a biochemist with knowledge of nuclear physics working for a research firm with government contracts. The project Banner was assigned to involved studying the surges of incredible strength people gain when angry or frightened. This project was of personal importance to Banner, as he had recently lost his childhood girlfriend, Julie Connors, in a traffic accident. Julie had been trapped in an overturned car when it caught fire, and Banner had been unable to free her. Banner wanted to know how it was that others could tap into this strength but he could not when it mattered most. During the course of the project, Banner hypothesized that certain external factors may play a part in gaining this extra strength during periods of stress. Cross-checking background gamma and cosmic ray emissions during the times of documented instances where normal people exhibited brief surges of enhanced strength, Banner discovered that a number of cases coincided with high points in the background gamma radiation received from the sun. Checking the date of the accident when Connors died, he discovered that day was a low period in the cycle. Deciding to test his theory without waiting for proper authorization, Banner subjected himself to what he believed to be a controlled dosage of concentrated gamma radiation. Unknown to him at the time, however, the equipment he was using had been modified by a coworker to produce nearly ten times the amount it was calibrated for. In most people, the amount of gamma radiation he received would have been instantly lethal. Banner, however, possessed an unknown genetic code similar to that possessed by mutants; it is entirely possible that Banner was a latent mutant, and the dose of gamma radiation he received mutated his DNA even further. At first, there were no known effects from the experiment; Banner was about to write off the experiment as a failure when circumstances changed.