in the movie was that a guy forgot his mask and didn't have a replacement, so stayed onboard.. in another couple,t he woman could no tequilas, so cam back onboard with her husband dive buddy.. So, the guy who forgot his mask talks the non-equilizing chick into loaning him her mask, then talks her hubby into being his buddy and going back on the dive.. so, I forget exactly what happened, but they took a diver count before the dive.. after all the confusion of who went, who stayed, who came back, and who then went diving again, the count got messed up.. I think they counted the two people (non-equalization couple) as coming back onboard, then forgot to mark off the mask forgetting dude and the ear chick's hubby when they left.. so, there was one actually onboard, but they had 3 counted a being onboard - out of something like 23-25 divers...
What's the moral of the story? Never dive with more than 4-5 people - big groups suck to begin with, and goofy diver counts ensue...
Friendship is like peeing your pants.. Everybody can see it, but only you can feel the warmth..