Really excellent entry, this was a ton of fun to play! The art is really good (love the little dance that the divers do), and the music intensifying when a shark starts chasing you is excellent sound design. And the gameplay itself is really fun; one thing I love about this is that you really don't need a map to locate the divers, because you can see sharks/divers in the distance based on the colored lights. That's smart design!
I think my two nitpicks are that I would've liked the camera to be able to show a wider view around the submarine, so I could see how close a shark chasing me is getting, as well as making the lights in the distance a bit brighter so it's easier to see. Sometimes lights would flicker and then disappear, so having them be brighter and more consistent would be a good touch.
Overall though, I have to say this is one of the best I've played so far. Really great job on this!