Warning: Major Shang-Chi spoilers ahead.
The mid-credits scene in Shang-Chi and the Legend of the Ten Rings catches up with the film’s central two heroes (Simu Liu’s Shang-Chi and Awkwafina’s Katy) in an impromptu meeting with Wong (Benedict Wong), Carol Danvers (Brie Larson), and Bruce Banner (Mark Ruffalo). Their conversation focuses largely on the mysterious tech powering Shang-Chi’s ten rings, but it’s Bruce’s appearance that has spawned the most conversations amongst Marvel fans.
Why? Because Bruce isn’t in his Professor Hulk form in Shang-Chi. Instead, he’s just his normal human self, albeit one still stuck wearing the same sling he’d previously donned at the end of Avengers: Endgame. Given how happy he seemed to be living permanently as The Hulk, his return to his human form left many fans confused and curious about what might have caused the change.
Fortunately, one Marvel fan may have already figured out the reason for Bruce’s appearance at the end of Shang-Chi.
Oh, Hey Bruce — Bruce’s decision to revert back to his human form — as seen in Shang-Chi — may have everything to do with his role in Marvel’s upcoming She-Hulk Disney+ series, according to Redditor u/cosinecasino.
The series is set to introduce Jennifer Walters (Tatiana Maslany), Bruce Banner’s cousin in the comics who becomes She-Hulk after receiving a life-saving blood transfusion from Bruce himself. Ruffalo is confirmed to be appearing in the series, and the Redditor believes that Bruce may revert back to his human form in the series in order to give Maslany’s Jennifer the same blood transfusion that turned her into She-Hulk in the comics.
Bruce’s Role in She-Hulk — This is an interesting theory and — because we already know that Ruffalo will appear in She-Hulk — it holds more weight than most of the Hulk theories circulating online right now.
Notably, it’s already been established in the MCU that regular materials (like, say, needles) cannot pierce the Hulk’s skin, which means Bruce wouldn’t be able to give anyone a blood transfusion while in Professor Hulk form. In the comics, Jennifer Walters is attacked and shot while with Bruce, which is what prompts him to give her a last-minute transfusion of his own, gamma-irradiated blood.
All of this is to say that, if Marvel does stick fairly close to Walters’ comic book origin story in She-Hulk, it seems likely that it’s in helping his cousin that Ruffalo’s Banner decides to turn back into his human self in the MCU. Of course, that would also mean that Jennifer Walters has already turned into She-Hulk by the time we see Bruce in Shang-Chi — making the She-Hulk TV series one of a growing number of Phase Four titles to take place just a few months after the events of Avengers: Endgame.
The Inverse Analysis — There’s a very high chance that the explanation for Bruce being his human self in Shang-Chi won’t be revealed by Marvel until She-Hulk premieres on Disney+. As a result, there’s no way of knowing whether or not this theory will ultimately turn out to be true.
That said, it makes sense given everything we know right now about She-Hulk and Bruce’s role in it (which is, admittedly, very little). This is also a fairly neat explanation for one mystery that Marvel fans are blowing a little out of proportion, which means it’s probably closer to correct than many of the wackier theories other fans have thrown these past few weeks.
Shang-Chi and the Legend of the Ten Rings is playing in theaters now.