Research scientist David Banner (Bill Bixby), haunted by the loss of his wife Laura in an automobile accident, studies alongside fellow researcher Elaina Marks (Susan Sullivan) the phenomenon of regular humans suddenly becoming capable of great strength during duress. Upon learning that gamma radiation emitted in sunspots had affected his cases' DNA structure, David decides to subject himself with a concentrated dose of gamma rays to help increase his capacity of strength. Unbeknownst to him, the machine he uses had been re-calibrated and it ends up giving him a much higher dose than expected.
When it seems like nothing had changed, a frustrated David heads to his car to return home, in the middle of a torrential thunderstorm. However, his tire blows and he has to fix it. The increasing anger over his (seemingly) failed experiment and inability to replace his tire amidst an unrelenting downpour ends up boiling over and it causes a strange transformation. David morphs into a muscular, primitive green-skinned giant (Lou Ferrigno, with growls and roars done by Ted Cassidy) driven by pure rage and is inhumanly strong. The creature that was once David Banner demolishes the car and wanders into the woods.
The next morning, the thing encounters a little girl fishing in a lake. The girl, terrified over the green beast, rushes into a canoe and falls into the water. The creature attempts to save her from drowning, but the scared girl screams for her father. Taking notice of the commotion from afar, the girl's father pulls out a shotgun and shoots the beast in his shoulder. Enraged, the creature rushes to the father, breaks his shotgun and hurls him into the water where his child is. With the little girl saved and her father relatively unharmed, the creature calms down as he wanders further in the forest and soon transforms back into Dr. Banner.
David heads to Dr. Marks' apartment in a daze, where she is shocked to find his clothes in tatters and having a gunshot wound. David has no memory of what happened the previous night, except feeling incredibly strong and seeing his eyes completely white in a stream. Wanting to figure out what had happened, David and Elaina head back to the Culver Institute and figure out the mystery of David's possible affliction. Marks places Banner in a hyperbaric chamber to recreate the events of last night and see what triggered his transformation. After some failed attempts, David ends up falling asleep and has a nightmare about Laura's death. Waking up, he transforms back into the creature and begins wrecking the chamber. A frightened and astonished Elaina watches as the beast tears through the chamber and frees himself. She does manage to calm him down and take a blood sample from him.
Now learning that a strong emotional reaction (usually anger) is what causes the transformation, David and Elaina debate whether or not the creature can be a threat; David believes that the creature has little to no emotional control and could kill someone while Elaina believes that, despite his destructive nature, he is still David in some way and won't kill anyone. They soon attempt to find a way to cure him of his condition. Jack McGee (Jack Colvin), a tabloid reporter the scientists have encountered before, comes to the institute with a state trooper. He relates a story told by the hunter and his daughter of a "big hulk" who terrorized them and wonders if they know anything about it, which they deny. However, McGee grows suspicious of the two and sneaks into their lab. Hiding in the closet, he overhears David and Elaina talking about leaving the Institute and experiment in a safer place, with Dr. Banner suggesting creating a fortified radiation vault to hold their "friend" if he ends up coming out. The scientists quickly catch McGee eavesdropping and David escorts him out of the building, but not before the snooping reporter accidentally knocks some dangerous chemicals over.
As David and McGee almost have a tense discussion, which is quickly ended by the former cryptically warning him to not make him angry, the chemicals leak into a pile of sacks labelled "DANGER". As soon as Elaina notices this, the building explodes and knocks the two men down. David rushes to the burning building to rescue Elaina, but the fires are too strong and intense for him to even see her inside. They eventually trigger his transformation into the creature, who notices Elaina unconscious and trapped in rubble. He leaps into the building, lifts the rubble off her and carries her out of the building. As the two wander in the forest, Elaina soon dies from her injuries in the fire, but not before admitting to David's other half that she had always loved the man and always will. The creature howls in anguish before leaving her body behind.
Days later, an injured Jack attends the funerals for Drs. Marks and Banner. Upon witnessing the creature, that he now dubs "The Incredible Hulk", carry Elaina out of the fire earlier he assumes that he is responsible for their deaths and wrote a story about it for his paper. He even admits to a co-worker of theirs that he gave the Hulk's description to various law enforcement agencies and that, if captured, he will be considered the biggest story in the century. As everyone leaves the proceedings, David appears and walks up to Elaina's gravestone, telling her that he loved her as well....even though she never said the same (he doesn't remember that Elaina did say it to him, but only when he was the Hulk). Carrying nothing but a dufflebag, David walks away, beginning his years-long trek to find a cure for his terrible condition.
Tropes pertaining to The Incredible Hulk
- Dying Declaration of Love: Before succumbing to the injuries she suffered in the explosion, Elaina tearfully admits to the Hulk that she was in love with David and that she always will.
- Early Installment Character-Design Difference: While not as jarring as some other examples, the Hulk looks noticeably different than he does later in the series, as his hair is slightly longer, his eyebrows are bigger and stick out further, and his skin has a bit darker tone of green. His look was subtly toned down after the second pilot and became more or less set in stone in the series proper, with the fourth episode being the final time remnants of the original design are present.
- Early-Installment Weirdness: The hunter's daughter is the only child in the entire series who seems afraid of the Hulk. Likewise, David's first transformation also lasts much longer than would become standard for the series.
- The Lost Lenore: David's late wife, Laura. Her tragic demise from a car accident still haunts him (especially after he becomes the Hulk) and drives him into studying humanity's hidden potential for super-strength (mainly to figure out why he wasn't strong enough to save her).
- Mirror Reveal: After his first transformation into the Hulk and back again, David sees his reflection in the edge of a stream and notices something different about himself for a brief moment. Later recounting the event to Dr. Marks, he says, "My eyes were white." Little did he know...
- Origins Episode: This episode details how David Banner becomes the Hulk and how he ends up on the run.
- Papa Wolf: The hunter shooting at the Hulk. Of course, he didn't know he was actually trying to save his daughter, but seeing her scream in fright as a giant, green monster holds a tree toward her as she was drowning made him understandably think otherwise.
- Pilot Movie: It originally aired as a two hour TV film, along with Death in the Family.
- Shout-Out:
- The scene where the Hulk meets the little girl is a homage to the first Universal Frankenstein (1931) movie.
- The scene where the injured Hulk looks at his reflection is an homage to Bride of Frankenstein.
- Skyward Scream: Distraught at Elaina's death, the Hulk sorrowfully roars to the sky, it echoing across the forest.
- You Wouldn't Like Me When I'm Angry!: This immortal line is used here, as David escorts Jack out of the Institute after catching him sneaking around.Jack McGee: If you know anything about this creature, it is your duty to report that to the police!
David Banner: You're letting your imagination run away with you. Now, I have never seen this creature that you're talking about.
Jack: Forgive me, doctor, but I am calling you a liar.
David: (agitated) Mr. McGee! (beat, manages to calm down) Mr. McGee.... don't make me angry. You wouldn't like me when I'm angry.
