- Spider-Man (Peter Parker) (First full appearance) (Main story and flashback)
- Daily Bugle (First appearance)
- Aunt May Parker (First appearance)
- Debra Whitman (First appearance)
- Lizard (Curt Connors) (First appearance) (Main story and flashback)
- Subway repairmen
- Eddie Brock (First appearance)
- Lawrence Kim (Named only) (bank manager)
- Margaret Connors (First appearance)
- Billy Connors (Only appearance)
- Ned Leeds (Named only)
- Fantastic Four (Mentioned)
- Avengers (Mentioned)
- Hulk (Bruce Banner) (Mentioned)
- Defenders (Mentioned)
- Spider-Man's Suit
- Spider-Man's Web-Shooters
- Spider-Man's Utility Belt
- Neogenic Recombinator (First appearance)
- Subway repairmen's van
- Police cars
- Public bus
Subway repairmen Sam and Bud are attacked by a reptilian creature. Sam is kidnapped, while a terrified Bud flees, driving dangerously on the road until Spider-Man saves him when his van plunges into the water.
At the Daily Bugle, Robbie Robertson tells Peter of a giant lizard terrorizing New York City, and J. Jonah Jameson informs Peter and Eddie Brock that he is offering $1000 to anyone who can get a picture of the creature. Initially dismissing the Lizard's existence, and believing it to be an urban myth, Spider-Man is surprised to find large reptilian footprints in the subway.
Peter decides to take the photos of the footprints for analysis by Dr. Curt Connors, but he and Debra Whitman find the reptilian creature fleeing Curt's office, with Connors nowhere to be found. Spider-Man visits Curt's wife, Margaret. However, he is distracted by Eddie Brock getting attacked by the Lizard outside. Spider-Man subdues the creature, causing it to flee. Margaret then tells him that Curt is the Lizard; he was transformed after attempting to re-grow his lost arm with the 'Neogenic Recombinator'. Meanwhile, Brock is eavesdropping in the background. He takes off to produce his story, but Spider-Man chases him and webs him to a lamppost to prevent him from ruining Connors' life.
Spider-Man returns to find that Mrs. Connors has been kidnapped and taken into the sewer by the Lizard. He follows them and finds the missing subway worker trapped. Curt tells Margaret that he plans to use the Neogenic Recombinator to transform everyone in New York into reptilian creatures like him, in order to create a new super race where everyone would be able to heal any wound or replace any lost limb. Having overheard his plan, Spider-Man attacks the Lizard. As they fight, Spider-Man steals the Recombinator, but the Lizard causes them to plunge into the water. In the ensuing struggle, Spider-Man manages to use the Recombinator to transform Curt safely back to his human form.
The following morning, after Peter has already handed in photos of the Lizard, Eddie Brock tells Jameson that the Lizard is Curt Connors, but the idea is dismissed after they knock on his door to be answered by Connors in human form. Meanwhile, Peter gives his $1000 bonus to Aunt May to help pay the bills.
|Peter Parker/Spider-Man||Christopher Daniel Barnes|
|J. Jonah Jameson||Edward Asner|
|Aunt May||Linda Gary|
|Joe "Robbie" Robertson||Rodney Saulsberry|
|Debra Whitman||Liz Georges|
|Eddie Brock||Hank Azaria|
|Dr. Curt Conners/Lizard||Joseph Campanella|
|Margaret Conners||Giselle Achecar|
|Billy Conners||Toby Ganger|
- The episode is loosely based on Amazing Spider-Man # 6.
- Adapted into comic book format in Spider-Man Adventures # 1.
- The episode aired as a preview of the series several months before the next episode.
- During the episode, Spider-Man comments on how his missions often involve him entering the sewer, and he remarks that it would never happen to the Fantastic Four, Avengers, or the Defenders (but maybe the Hulk).
- The newspaper article detailing Spider-Man's fight with the Lizard is credited to Ned Leeds.
- The Connors' family name is given as "Conners" on the plaque outside their home and in the episode's voice actor credits, whereas the former spelling is only present on Curt's office door at the university (although an earlier scene shows the door labelled "CONNeRS" instead).