In the latest issue of "Civil War II," in which the superhero alliance the Avengers -- popularized by Marvel's staggeringly successful movies -- are divided into two opposing teams, Banner's comrade Hawkeye shoots the Hulk's human alter ego in the eye, killing him.
It's a mercy killing, it turns out -- Banner had given the marksman a special arrow and instructions to kill him if he looked certain to go on a rampage.
Banner has been hulking out in Marvel comics since 1962, when he was created by Stan Lee and Jack Kirby, caught in a gamma explosion and given an impossibly powerful alter ego.
But the un-killable Hulk -- or at least his mild-mannered human analog -- has now been brought down.
In the superhero version of an intervention, the team lures Banner -- who has been taking Hulk-supressing medication -- outside and, even though he has yet to cause the kind of mass destruction he's famous for, is killed.
"Oh my god," says Banner, to find a host of heroes on his doorstep. "What -- what did I do?"
Avenger Tony Stark replies, "That's the thing, Bruce. You haven't done anything..."
"Yet," adds Medusa. And then, in the language of comic books -- Pow! Hawkeye's arrow takes down the scientist.
"This is uncharted territory for us," Marvel's editor-in-chief Axel Alonso is quoted as saying
in the New York Daily News.
"Only two things are for certain: It will take a long, long time for our heroes to come to terms with his loss, and the circumstance surrounding his death will leave a huge scar on the superhero community."
It's not exactly uncharted territory -- comic book publishers routinely kill off and resurrect their superheroes -- in an attempt to keep fans engaged and buying books.
In the aftermath of "Civil War II's" predecessor, 2006's "Civil War," Steve Rogers' Captain America was killed and his longtime friend Bucky Barnes takes over the job for a spell. More recently, his friend Sam Wilson -- previously the Falcon -- took over the red, white and blue shield.
Spider-Man has also recently died and of course, the grand-daddy of all superheroes, Superman, was killed off in the early 1990s, only to fly back into the hearts and minds of fans faster than a speeding bullet.
And even if Banner does -- improbably -- remain dead, the Hulk mantle has already been passed on, this time to a Korean-American teenage genius called Amadeus Cho.
It's part of a move -- which many fans say is long overdue -- to diversify the genre. Spider-Man is now Miles Morales, a black-Hispanic teenager, Thor a woman, Ms. Marvel a Muslim and fans recently learned that the Iron Man suit will soon be inhabited by
an African-American female teen named Riri Williams.