Young diver is in the water and begins to slowly descend, so nice. Watch the whole thing to see how quickly things can go from idyllic to life threatening while diving.
For the impatient, at around 3:30 or so he gets caught in a wall downcurrent, and a minute and a half later he's in trouble and crying for help. Also watch the bubbles -- they aren't floating up, you can see other divers getting swept down the wall face as well, strong current and no one can fight it. This youngin is lucky that a more experienced diver finally gets to him to help, I think he would have been a goner. Finally they move away from the wall, but the youngin rockets up too fast, now the more experienced diver tells him he's got to go back down before he bends.