Issue Detective 627
Subtitle The Case of the Chemical Syndicate (4 takes on the first ever Batman story: the original, the thirtieth anniversary edition, and two new versions)
Date March 1991
Writer(s) version 1: Rob't Kane version 2: Mike Friedrich version 3: Marv Wolfman version 4: Alan Grant
Artist(s) version 1: Rob't Kane version 2: Bob Brown, Joe Giella version 3: Jim Aparo, Mike DeCarlo version 4: Norm Breyfogle, Steve Mitchell
storyline version 1: Batman stopped a killer who was attempting to take over a chemical company by killing off his partners / co-owners.
version 2: Batman and Robin tracked down a killer who took down two chemists working on war technologies. It turned out to be a member of the team trying to get sole ownership of their discovery. 
version 3: Batman showed up on the scene after a chemical plant big-shot was killed. The man was melted into his taxi by someone spraying toxic waste. A second was killed along with his wife and some innocents by this new villain, Pesticyde. Batman found out the third of the four owners was crippled from an accident at the plant. He stopped the man's daughter before she could kill her father's last living partner. 
version 4:
Batman and Gordon investigated when a top chemist was found dead. Batman witnessed a second one die and caught the killers. They'd been hired by the partner of the two dead men. Gordon found the third hanged with a note. Batman knew it was no suicide - the real killer attacked and fell into a vat of chemicals and died.