Bruce Banner's assistant Randall Jessup has been kidnapped by Dr. Ted Goodrich. He's keeping Jessup in a secret facility where Goodrich is experimenting to enhance the human race. Something similar to what years ago was done in the Beehive lab (which failed).
The facility is powered by a core that's unstable. Goodrich and his assistant Dr. Stella Webb dismiss Jessup's concerns.
Outside, the Incredible Hulk and the rest of Banner's assistants (Daman Veteri, Melinda Leucenstern, Patricia Wolman), wear teleport bracelets to infiltrate the facility, following the Hulk. As this happens, Jessup turns into its monster form, which feasts from hate and rage, and the Hulk has plenty of that.
As the facility is being destroyed, Goodrich opens a cocoon that hosted an experimental being, despite Webb's concerns. From it comes a monster who grabs both, and traps them inside the coccoon.
Meanwhile, Jessup the monster, and the Hulk are hitting the facility's power core. Jessup causes the Hulk to turn back into Bruce Banner, and then he manages to make the core explode. Jessup turns back into his human form. Banner asks his assistants to stay hidden in this facility, and take care of Jessup.
Later, when Bruce Banner is interrogated by Maria Hill, he does not tell her about the facility, and denies knowing where his assistants may be. Maria does not believe him, and gets angry at Banner, who asks her to fire him. Maria acknowledges that cannot terminate him because he knows too much; instead, he should be "terminated". Banner takes it as a joke.
Back in his lab, and while recording his thoughts, a woman sneaks from behind and shoots him in the back of his head. Banner falls unconscious in a bath of blood.