World's Finest is a three part episode of both Superman: The Animated Series and The New Batman/Superman Adventures. It was shown and released on video as "The Batman/Superman Movie."
These episodes, listed on the website Batman-Superman.com, as episodes 039, 040 and 041 as per production assigned numbers, but were actually produced before the season one of The New Batman Adventures. The page also places the Superman: The Animated Series episode "Knight Time", which is supposed to be after "World's Finest", between episode 018 ("Old Wounds") and 019 ("Legends of the Dark Knight").
The Joker steals a Chinese statue known as the "Laughing Dragon" thought to be made of jade, but Batman analyzes a fragment and finds it is actually solid Kryptonite. In Metropolis, Joker tells Lex Luthor he is broke due to Batman's success in closing down his operations, and offers him a deal: for one billion dollars, he'll kill Superman.
Bruce Wayne happens to be visiting Metropolis to work with...
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