This post contains spoilers for Spider-Man: Brand New Day. If you want to avoid them for now you can instead check out our non-spoiler review.
Spider-Man: Brand New Day‘s trailers didn’t just promise a fight between Spidey and Hulk. The movie promised a fight between Spidey and the big green rage monster of old times. How and why did Dr. Bruce Banner lose control and revert to his pre-Professor Hulk form? After his inhibitor broke something broke inside of him. What pulled him back is good new for Peter Parker.
After Thanos’ Snap, Bruce Banner “put the brains and the brawn together” to create a single combined persona. We first met the MCU’s Professor Hulk in Avengers: Endgame. That seemed to mark the end of Hulk as we knew him forever. Professor Hulk didn’t stay that way for long, though. In a Shang-Chi and the Ten Rings post-credits scene, Banner was back to his old human self. That sequence showed him wearing a device on his wrist. In the opening moments of She-Hulk, he told his cousin Jessica Walter it was an inhibitor device. It keeps his gamma radiation muted so he can stay human.
A desperate Peter Parker went to speak (in code) with Dr. Banner in Spider-Man: Brand New Day about controlling his own, suddenly changing powers. After learning about the inhibitor device and how it prevents Hulk from coming out, Peter then built a specialized one for himself. It controlled (so long as it didn’t overheat) his arachnid DNA. Despite Banner pointing out the danger of such a device, Peter also made a universal one so he could stop Jean Grey from using her powers.
When Peter arrived at Damage Control to stop the mutant, he found Professor Hulk ripping the building apart. Jean had used her psychic powers to control Banner. She had him remove his inhibitor chip and destroy it so he could tear the walls away from the locked door she wanted to get into. While not in control of his actions, at that point Hulk was still his smart, professor persona. It was only after Jean got out of his mind and he briefly returned to his human Banner form that things got bad.
Banner asked if he’d hurt anyone, but when Peter tried to place the universal inhibitor chip on the professor so Jean Grey couldn’t get use Hulk again, Banner refused. Then he got angry. He told Peter the mutant had “broken” something inside of him. He lost all control, telling Peter, “No Banner. Only Hulk.” But not Professor Hulk. We then, after 14 years, saw Bruce Banner Hulk out on screen. He reverted to his old, uncontrollable Savage Hulk form.
The ensuing fight was brutal and destructive, as Peter did everything he could to tie Hulk down with webs. It was all he could do after the green monster’s skin proved too thick to place the inhibitor chip. Ultimately Hulk had Peter by the throat ready to end the battle for good. It was at that moment Spider-Man looked at his old superhero ally and revealed his true identity. He said it was him, Peter.
Dr. Bruce Banner had not recognized Peter Parker when the young hero had arrived at his university asking about suppressing superpowers. But in that brief moment Hulk did know Peter. Deep down on some level, Hulk recognized Peter Parker as a friend. It stopped Hulk completely. He let Spider-Man go and went back to being Bruce Banner.
Hulk’s recognition of Peter Parker’s name is the best news Spider-Man has had in years. Combined with Ned innately remembering their best friend handshake, there’s enough evidence to believe Dr. Strange’s spell, the one that made the world forget Peter Parker, isn’t iron clad or eternal.
Not that Bruce Banner has any idea what any of that means. Or who Peter is. He’s currently in a psychiatric ward. The story being told is that he had a mental breakdown. Not great for Bruce, but at least the people of New York City won’t have to worry about Hulk smashing anything anytime soon. But Peter Parker knows the truth, just as Hulk knows Peter Parker.