When David explores the area where his father was diving, he finds an underwater cavern which opens up into a secret room. The path through the cavern is filled with booby traps like in Indiana Jones, but not as competent. The traps are easily avoidable since the triggers seem to be a foot ahead of where the actual death traps deploy. So they swing or protrude harmlessly in front of David.
The Italian Gene Simmons, 0part of the Mafia who David's father was working for, tries to make David an offer he can't refuse. Somehow David refuses it and soon his girlfriend is kidnapped in a bid to force him to take them to the treasure. I'm left thinking the sharks are just an afterthought added onto a movie which reads quite a bit like an low rent Indiana Jones script.
Let's see... father disappears on an expedition, looking for treasure from Crusades, main character is a professor who searches for long last antiquities, he finds a cave with booby traps and treasure, villain tries to force him to reveal location of treasure, etc. Yup, just add sharks and it's a different movie.
And where else can you see someone blow up a shark?