James Cameron finally got his big break in 1981 when he got his first shot at directing a film entitled Piranha II: The Spawning. Italian producer Assonitis, was determined to produce a sequel to the original Piranha film. In an effort to save money and have complete control over the film's direction, the inexperienced Cameron was chosen. However, Assonitis and Cameron just ended up butting heads by the time the movie's release came around.
The movie was to be produced on Jamaica but when Cameron arrived at the studio, he discovered that his crew was comprised primarily of Italians who spoke no English and that the project was under financed.
James Cameron was originally hired as the special effects director for this film and took over the direction when the original director left. Due to budget limitations the crew was composed essentially by Italians, none of whom spoke English. Some however did have prior experience on horror/fantasy movies so they were, to some extent, able to satisfy Cameron's requirements.

After the first week of shooting, the set harmony was disturbed by some discussions about the work between the director and the producers (the executive producer, Ovidio G. Assonitis, asked to verify the day-to-day activities, arguing most of Cameron's choices), so whilst Cameron was just responsible for the shooting, most of the decisions are under Assonitis' authority. On the T2 special edition, Cameron speaks briefly about his time on this film. He says he worked for two weeks on PIRANHA 2 before being fired by Ovidio Assonitis (Oliver Hellman) who finished the film. Hellman did this a lot on his productions, firing the original director and taking over himself. Cameron was not allowed to see his footage and was not involved in editing.

The original director of Piranha II was Miller Drake. Drake was yet another Corman graduate who had labored alongside Joe Dante in the New World trailer department—and had essayed the role of “First Mutant” in Dante’s directorial debut, Hollywood Boulevard—before becoming Corman’s de facto head of postproduction. “Jeff Schechtman said, ‘Would you like to direct this movie?’ and I said, ‘Sure,’” recalls Drake. “We met with Ovidio Assonitis and he said fine.” Drake set to work developing a script with writer Charles H. Eglee. Before Rob Bottin could start his work on prosthetics, Assonitis removed Drake from the movie. “In the beginning, the package that I got from Chako and Jeff included also this director,” says Assonitis. “But I didn’t like him. I didn’t think he was right for the movie.” Miller Drake remembers things somewhat differently. “It was one of those things that kept going on forever,” he says. “We waited and waited. Then finally we had some big meeting in a hotel. Schechtman was with me, and we’re meeting with Ovidio. It was basically, ‘Are we going to do this movie or not? I’ve got Bottin and I’m going to lose him.’ And, you know, [Assonitis] is hemming and hawing, and it got a little heated up there. I got a call from Schectman about two days later. He said, ‘Come by, I want to talk to you.’ And I went to his office and he said, ‘Look, Ovidio is kind of upset about the other night, so you’re off the picture.’ I said, ‘Okay, that’s fine.’” Assonitis decided to replace Drake with James Cameron, who was an art director for Corman's movies. Assonitis himself says that he fired Cameron because “he did a lot of terrible, stupid things that are typical of a person that has not the experience.” Pressed to give an example, the producer recalls that when Cameron failed to get a close-up of an actress, he and his crew sailed off the next day to secure the shot. “He took the whole crew on an incredible cruise trying to get under a cloud to reproduce the lighting,” says Assonitis. “We had to spend the whole day running after the cloud on several kinds of boats.” The producer also says that after two weeks of shooting the film was “heavily over budget.”

Jeff Schechtman, on the other hand, paints Assonitis as the villain of the piece, describing him as “a major pain in the ass” who “fancied himself as a director.” However, Schechtman agrees that the principal reason for Cameron’s firing was budgetary


James Cameron: I'm ambivalent about it. Technically, I have a credit as the director on that film. However, I was replaced after two-and-a-half weeks by the Italian producer. He just fired me and took over, which is what he wanted to do when he hired me. It wasn't until much later that I even figured out what had happened. It was like, "Oh, man, I thought I was doing a good job." But when I saw what they were cutting together, it was horrible. And then the producer wouldn't take my name off the picture because [contractually] they couldn't deliver it with an Italian name. So they left me on, no matter what I did. I had no legal power to influence him from Pomona, California, where I was sleeping on a friend's couch. I didn't even know an attorney. In actual fact, I did some directing on the film, but I don't feel it was my first movie. So I don't think I should have to take the lumps. I used it as a credit when it did me some good, which was to get Terminator. Subsequently, I dropped it. I think that makes sense

Most of the underwater scenes were filmed off Grand Cayman Island, and the stand-in for the Club Elysium is the Mallard Beach Hyatt. Interior scenes were filmed on a soundstage in Rome

James Cameron: "[They gave me directing credit] against my will. I wanted them to take it off but they wouldn't do it. The release prints were made in Italy, at Technicolor in Rome, and I was in LA, so there was nothing I could do. (...) And I didn't even write the script. So the position I have to take is, it wasn't my script and I didn't really direct it. (...) You see, I thought it was actually going to be kind of a comedy. When somebody first told me the idea, and I had already seen the first film, which was a little bit tongue-in-cheek, I thought this could actually be interesting. You know, somebody is walking down the sidewalk, they get hit by a cloud of flying piranha, and three seconds later a steaming skeleton hits the ground. It could be kid of funny, in a real macabre, George Romero kind of way "(Dark Side magazine 1992)

Only two scenes have been confirmed to be shot by James Cameron. According to Cameron in The Futurist, it's the morgue scene and an outdoor daylight scene on the ocean according to Entertainment Weekly. Some sources cite the underwater scenes as well, however those have been unconfirmed

The great thing about the experience was that Cameron, under duress, in a feverish comatose stage, had a nightmare about an intricate metal skeleton rising from the fire like Phoenix... a.k.a. Terminator - his first brainchild and real directorial debut.

Piranha II credits. According to Cameron, the movie was written by Charles E. Eagle under the pseudonym H.A.Milton