Hmmmmm. That might have worked as well. But at this point I don't think it would be a good idea to confuse the audience anymore than they might be already. I think the best bet, and my dream opening, would be with the count down Having already started *que dreamy music*
ten minuted until gamma detonation Dr. Banner, all levels in the green. Good Igor, all precautions have been made, disabled. all fail safes and commence with the countdown, Banner looks through the binoculars at the test site and is shocked to see a car racing across the test area. Stop the countdown, theres a person driving across the test area.! yes Dr. Banner. Ill drive out there and get whoever that is into the secondary bunker. Banner leaves. Igor say to himself, Banner wouldnt share his research with me, he doesnt make mistakes. Ill show him a mistake. The countdown continues. As Banner gets closer to the trespasser he hears the countdown continuing T-minus two minute Good L Lord He say as approaches the young man. You fool! Youre trespassing on a government test area. The bomb is going to be detonated in less than two minutes! Chill out dude, I just won $100. $100 isnt going to do you much when youre dead. Hurry, we can just make it to the bunker. T-minus 5, 4 Get in there. Banner throws the young man into the bunker and looks back at the bomb. 3, 2, 1. The screen goes black for 10 second and bright white and slowly begins to rumble. Then a huge explosion and Banner wake up, his eyes white as he beings to Hulk-out.
Thats what Id like to see in the first five minutes. Then the story starts in the present. See simple

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