FLORIDA — The U.S. Coast Guard is searching for a Canadian movie director and conservationist who went missing in waters off Miami. <br /> <br />CBC reports that on Tuesday, filmmaker Rob Stewart went diving with a small group of people near Islamorada, in the Florida Keys. <br /> <br />The group dove nearly 70 meters to the wreck of the Queen of Nassau, and were filming for the sequel to Stewart’s award-winning 2006 documentary Sharkwater. <br /> <br />The Miami Herald reports that Stewart surfaced at around 5:15 p.m. along with a fellow diver, who passed out as he got on the boat and required attention from the crew. <br /> <br />By the time the crew was ready to retrieve Stewart, the filmmaker had gone back under. The crew was unable to locate him and contacted the Coast Guard for help. <br /> <br />Two boats and a helicopter were dispatched to the area to search for the missing diver but have yet to find him. <br /> <br />The dive Stewart was on was particularly difficult. Though experienced, his family believe it may have taken its toll on him after the third try, leading him to lose consciousness.