After a couple of early 1970s shows that became enormous blockbusters --Love Story, The Godfather -- Universal's Jaws dominated the summer box office in 1975, inaugurating the trend toward massive crowd-pleasing event movies. The big direct follow-up to Spielberg's shark attack picture was 1977's The Deep, another seagoing adventure starring Robert Shaw and based on the best-seller by the Jaws scribe, Peter Benchley. In June of 1977 nine out of ten moviegoers could probably be found lining up for Star Wars for the 4th or 5th time. But just down the street The Deep was doing respectable business as well, earning back 2/3 of its nine $ million budget in its first weekend.

The Deep is a commercially conceived, professionally filmed action thriller with a very weak story. On the plus side are good performances from attractive stars, plus some truly outstanding underwater cinematography. But even patient audiences balked at buying a plot that just didn't seem to make much sense. Today, of course, action thrillers are so lame-brained that The Deep now gets above-average marks for sophistication.

Romantic vacationers Gail Berke and David Sanders (Jacqueline Bisset & Nick Nolte) dive on the wreck of the WW2 steamer Goliath, finding samples of two kinds of treasure -- a Spanish medallion and an ampoule of morphine, one of thousands being sent to the front lines in Europe. They're soon accosted, and then threatened by Henri Cloche (Louis Gossett), the local Haitian crime lord. Seeking aid from famed treasure hunter Romer Treece (Robert Shaw), Gail and David join forces to collect the morphine (to buy off Cloche) while investigating a second wreck of an 18th century treasure ship. But skullduggery is afoot -- Romer's pal Adam Coffin (Eli Wallach) is feeding information to Cloche behind Romer's back.

The Deep can't be beat for diverting entertainment. The Bahamian locations are as beautiful as the actors, who give their thinly written parts considerable star-power depth. Robert Shaw is an educated, less salty version of his shark hunter from Jaws. In his feature breakout role, Nick Nolte is masculine and intelligent, and quite likeable. Jacqueline Bisset is a spirited and capable in the role of "the girl" in a masculine adventure. Bisset is also the film's most impressive special effect -- she plays the entire first episode in a wet T-shirt, which is enough to make most males light-headed. It's a clear victory for the talented Bisset -- she's such a classy actress that she transcends definitions of exploitation.

About a third of The Deep takes place underwater, in scuba-diving scenes that still haven't been beaten. In the extras we discover that the three stars and director Peter Yates did their own underwater work, even some of the stunts. Most movie scuba scenes eventually lapse into boredom, even in the James Bond movie Thunderball, the previous champion in the swim fins 'n' bubbles genre. Yates and underwater director Al Giddings build terrific sequences in the wrecks of sunken ships. We don't need expository voiceover -- careful direction allows us to follow everything that goes on quite clearly.

The production is so attractive that we're over an hour into the show before questions of common sense arise. I remember audiences laughing at the ability of the divers to communicate in one scene, just by "shouting" underwater. The film's overall technical credibility keeps me from calling it an oversight. But a number of other questions arise to undermine the film's overall effect.

Romer Treece lives in a trendy converted lighthouse just a couple of miles from a fabulous unexplored wreck that lies within sight of a resort hotel. Everyone knows that the Goliath contains a fortune in drugs because Adam Coffin was one of its crew. The wreck has been off limits because of the danger of munitions on board. In thirty years, nobody's blown up the wreck to remove a threat to nosy tourists. Romer is able to work over the wreck for days on end without drawing any local law enforcement. The movie claims that the treasure has been uncovered only recently, but we think Romer and Cloche would have been out there looking anyway.

Gail and David are kidnapped and threatened; Gail is strip-searched and terrorized with a voodoo ritual. Yet the couple calmly goes about their treasure hunting. David even leaves Gail alone and unprotected in her hotel room knowing that Cloche's hoods are at large. `977 audiences didn't buy that at all. They were also amused by the casual portrayal of the bad guys as sinister blacks. Live and Let Die had an all-black gang of criminals, but it was a comedy and at least half the jokes were on James Bond. The villains in The Deep are all colorless nobodies except for Louis Gossett, and he isn't very clever either.

Finally, we aren't sure what Romer & Co. intend to do with the zillions in hot morphine. The Deep underplays its drug angle but the trio certainly seem to be risking letting all that dope get on the market. The adventure is pretty much a criminal enterprise even for the heroes, and Peter Benchley's story doesn't seem to have an opinion about that one way or another.

As long as one accepts the TV mystery plotting The Deep is very enjoyable. The film uses a giant Moray Eel as sort of a Serpent Ex Machina, but it has a terrific shark attack scene among its numerous underwater thrills. The three treasure hunters do some fun historical searches in Romer's library. Not only does Romer possess original manifests and other Castillian gold shipment records, all three heroes apparently read archaic Spanish! And there's some vicarious fun in the belly of a sunken ship, using a dredge vacuum to suck the sand away from a fortune in bobbing bottles of dope. We immediately identify with David when he drops his facemask to squeeze through a narrow slot to reach a priceless gold bauble poking out of the sand.

A question for drug-o-philes: does liquid morphine have an expiration date? It would be fun to see Cloche murdering half the island to secure possession of the dope, only to find out that it has all turned to sugar water. That's a problem worth investigating. You go ask your pharmacist. I'll check out the first underwater scene in The Deep again, just to see if there are any clues there. Maybe I'll watch it two more times, to make sure!

Sony's Blu-ray of The Deep is a viewing pleasure -- two hours of exciting action in an exotic location without a trace of CGI. Good action thrillers have become so rare that The Deep's modest virtues shine in comparison. The actors really swam, in real water! The producers had to go to Australia to film the shark scenes! It's (gasp) a real movie.

The HD picture looks great all around. Colorful fish surround the divers as they snoop for buried treasure, and the enormous close-ups of Ms. Bisset revive Old Hollywood notions of glamour. Composer John Barry's main theme isn't very memorable but nobody betters him for dreamy underwater atmospheres ... his shifting tones improve on his already sterling work for .