HISTORY: Morris Bench (a.k.a. Hydro-Man), a crewman on a cargo ship, gained his incredible abilities when he was accidentally knocked overboard into the ocean by Spider-Man, who was onboard the same ship. As he fell into the water, the experimental generator his ship was lowering into the ocean began to malfunction, exposing him to unknown levels of energies, seawater, and underwater volcanic gases (Read Amazing Spider-Man Volume I, #211-212 for further details). Upon his rescue, he realized he could transform all or part of his body into water. Furious at what had just happened to him, he set off for vengeance on Spider-Man and all those he considered responsible for his condition.

When Spider-Man first encountered Hydro-Man, he had a rather difficult time defeating his opponent since the latter was and still is virtually untouchable. However, Spider-Man did manage to defeat Hydro-Man when he lured him onto the roof of a building and splattered him over an area that was large enough to evaporate Morris before he was able to reassemble himself.

Unfortunately, that was not enough to defeat him and he soon returned and joined forces with the Sandman to overthrow Spider-Man. However, a freak accident caused the two villains to merge into one huge mud creature.

Once Hydro-Man realized he was not cut for a solo career, he joined forces with the Beetle, Boomerang, the Rhino, and Speed Demon to form the Sinister Syndicate whose first job was to assassinate Silver Sable. Again, Spider-Man, with some help from the Sandman, defeated them.