Vendetta

"Vendetta" is the twenty-first episode of Batman: The Animated Series. It originally aired on October 5, 1992, and introduces Killer Croc.

Plot
A police ship escorts a very nervous convict, Spider Conway, to Gotham Harbor. Commissioner Gordon is confused why Conway is nervous as he's getting an early parole in exchange for testifying against Rupert Thorne. Detective Bullock explains that Conway's nervous about someone getting to him before he reaches the hearings. It turns out that Conway's fears are well founded as a strange man attaches a bomb to the boat and kidnaps him in the ensuing chaos. The officers are rescued but Conway is lost. Upon learning this, Bullock drops a toothpick and orders the bay to be dredged.

Batman goes on his own investigation around Stonegate and discovers a toothpick on the docks.

Back at the Police Station, Bullock is enraged to learn that he’s been taken off the case. Gordon explains that Thorne is a prime suspect and because of that, "a lot of ugly ancient history is bound to come up." Batman listens in on this conversation and decides to investigate Bullock. He sneaks into the police files and takes the one on Bullock. Just as Batman takes the file, Bullock comes in and discovers that it's missing.

After Batman returns home, Alfred discovers the file and reads that Bullock was suspected of taking graft from Thorne. Although the case was dropped, because Conway was working for Thorne at the time and was the one who gave the information which got Bullock in trouble and his discovery of the toothpick at the dock Batman suspects Bullock is to blame for Conway's disappearance.

Meanwhile, Conway wakes up in an underwater cave and is confronted by a mysterious individual whom he is very frightened of.

Batman goes to confront Thorne who reluctantly explains that he has nothing to lose if Conway talks. Batman decides to believe him and leaves. Bullock now seems to be the prime suspect. He goes to Gordon and explains his suspicions about Bullock. Gordon doesn't want to believe Batman's intuition and insists that Bullock would never turn bad.

Things get worse for Bullock, however, when "he" arrives at the police station dripping wet and breaks in to kidnap Joey the Snail. With a witness testimony against him, Bullock is arrested.

Back in the Batcave, Batman reads the news but decides to turn his attention to a small scale he found on the docks. Alfred comes in with Batman's dinner and is told that the scale, although reptilian in appearance, has a human cellular structure. Alfred is unconcerned and gives Batman his dinner pointing out "it's in a microwavable Croc." Reminded of the criminal known as Killer Croc, Batman realizes that Bullock isn't the primary suspect after all.

To confirm his suspicions, Bruce Wayne goes to the zoo and learns that crocodiles live in underwater caves. This is the final clue he needs to deduce the location of Conway and Martin.

Returning to Gotham Harbor, Batman goes underwater in the Batboat and finds that there is in fact an underwater cave and the two kidnapped criminals are there. Batman starts to free them but Killer Croc arrives and attacks. Having enhanced strength, Croc easily gains the upper hand over his enemy. Seizing the opportunity, the criminals make their escape but Batman manages to tie up Killer Croc and catches the crooks before they can escape. Croc himself escapes, though, and continues with his plans.

Batman returns to the Batcave and searches for articles about Killer Croc learning that he was once a freak show attraction, then a wrestler and finally turned to crime. Bullock was the officer who caught him and he was convicted on testimony given by Conway and Martin. Now that he’s escaped, he’s out for revenge.

With the two criminals returned, Bullock is released and Croc takes the opportunity to assault him in his car. However, Batman is also in the car waiting for him and manages to save Bullock. Croc escapes into the sewers and Batman soon follows after him. A brief fight ensues and though Croc has the advantage of strength and better lung capacity, Batman manages to get the upper hand by using his arsenal. Croc is soon knocked out cold and given to Bullock who takes him into custody. Bullock is confused why Batman helped him and is told that Batman thought he was guilty too.

The next day, Bullock is formally cleared of all charges and tells criminals to beware that he's back on the street "and ready to kick butt."