Scuba diver appears to be reading book underwater!
Scuba divers frequently run into other groups of divers as they explore reefs and the ocean world. It is not unusual to pass by a fellow enthusiast going the other way. Usually, a glance and a wave is customary. Sometimes they will even exchange a few hand signals to warn of concerns ahead or interesting creatures to be on the lookout for. In all cases, the divers you meet are looking around and are visually checking out their surroundings as they pass by. Exploring the underwater world is usually the main reason for venturing into it.
It is extremely unusual to meet one who is reading a book. In fact, it is unheard of. In over a decade of diving, Dave, who is recording this dive has never seen, or even heard of such a thing. So he couldn't resist recording this strange sight and swimming closer to get a look at what could have been such riveting reading that it could not be put down for even a minute.
But this diver very likely did not have his latest suspense novel or best seller with him. It's obviously a plasticized book of some sort that is meant to be taken 30 feet down. It seems he is training or working through some skills, or possibly he is training somebody else who isn't far away. the book must actually have a checklist or series of exercises needed to complete a certification.
While Dave records the diver reading his book, it becomes clear that he is being watched and recorded. With a slightly surprised look, he gives a nod and a polite wave before going right back to his reading.
Although he knows better, Dave can't help but chuckle at what appears to be a book that is simply too good to be put down.