OK, I watched the movie twice and read a whole bunch of the reviews posted here. So here's what we know:

Harry Moseby (Gene Hackman) is a private detective.

Harry's marriage to Ellen (Susan Clark) is on the rocks.

Ellen is cheating on Harry with Marty Heller (Harris Yulin).

Marty Heller was also the name of my pharmacist when I was a kid.

Harry doesn't know any of the other players he comes across until he meets them for the first time.

Harry is hired by Arlene Iverson (Janet Ward) to return her runaway daughter Delly Grastner (Melanie Griffith) home.

Marv Ellman (Anthony Costello) has done the horizontal tango with both mother Arlene and daughter Delly, though not at the same time.

Joey Ziegler (Edward Binns) and Quentin (James Woods) often work together.

Tom Iverson (John Crawford) and Paula (Jennifer Warren) live together and work a charter fishing (and smuggling) operation in Florida.

Marv Ellman is found dead in the water (not hyperbole) by Delly, who high tails it back home with Harry to her mother, without telling Harry who it was she saw dead.

Delly does tell Quentin she saw Ellman dead. (She used to do the horizontal tango with Quentin).

Shortly after, Delly dies in a failed car stunt with Joey Ziegler driving.

Harry believes Quentin rigged Ellman's plane to crash, and rigged the car Joey was driving that killed Delly, because he thought Quentin knew that Delly knew that he rigged Ellman's plane.

Harry finds Quentin dead in the water (not hyperbole).

Tom Iverson admits killing Quentin to Harry before knocking himself out by ramming his head into a pole.

Paula admits that she, Tom Iverson, and Marv Ellman were in the process of smuggling a Yucatan artifact piece by piece, estimated worth a half million dollars.

Harry and Paula set out to retrieve the latest artifact, with Paula scuba diving to bring it to the surface of the ocean.

Joey Ziegler, in an airplane, attacks Harry in the Iverson boat, and manages to shoot him in the leg.

Paula surfaces with the artifact as Joey lands his plane on the water.

Joey races his plane toward Paula and the boat, striking and leaving her dead in the water (not hyperbole),hitting the floating artifact causing the plane to wreck, and finally sinking with the plane and drowning.

Why did Joey attack Harry? I don't know. Does anybody?

Like Harry, I was left going in circles at the end of the movie.

Oh yeah, almost forgot - before it's all over, Harry does the horizontal tango with Paula.

It's a finely made movie, beginning with Michael Small's deliciously jazzy score which rolls along under the credits, using only rhythm and vibes. At more dramatic moments the theme is echoed by a mournful oboe. There are touches of Gil Evans and Gunther Schuller in the arrangements. The score could probably stand alone.

The performances vary from professional to considerably more than that. James Woods is his usual cocky hypermanic self but it fits the role. Edward Binns is a serviceable utility player. Jennifer Warren is given some lines suggesting she sees herself as homely, and it's true she's not gorgeous, but only by Hollywood standards. As it is, she's on the cusp, and she has a face that intimates character, and a nice figure to boot, though her delivery sounds more like suburban Connecticut than the Southern semi-trash the character is supposed to be. Melanie Griffith makes a very acceptable 16-year-old nympho who spreads sex around the way some other people spread good will. Susan Clark as Hackman's wife is adequate. She has an outre kind of beauty. She has a wide mouth and her upper and lower lips seem to be of identical shape. And she has the eyebrows of the Mona Lisa, which is to say none at all.

The truly outstanding performance is Gene Hackman's. He's always good without ever being bravura, but here he outdoes himself as Harry Moseby, the sleuth who's going to solve all the world's puzzles. I'll just give one example of what I mean. Watch him during the scene in which he's in bed with Clark, dipping marshmallows into the fondu and telling her the story of how he tracked down the father who'd left him as a child. He's never spilled the beans to her about this incident before. It's an intense scene. But Hackman doesn't weep or pull his hair and pound the pillow with his fist. He snickers awkwardly, makes a few feeble attempts at wisecracks, and stumbles over his words. His awkwardness masks the emotional intensity of the moment. Hackman doesn't feel the need to tell us more than that. Few self-sufficient grown men would. Well, one more example. Watch his response when Griffith, on first meeting him, asks directly, "How old are you?" Watch the way he combines a chuckle at her effrontery with a direct and unashamed answer to her question.

I need to mention Rosemary Murphy too. It would be criminal not to. We meet her as a selfish slut who only wants her daughter, Griffith, returned to her in order to deprive her divorced husband of Griffith's companionship. When Griffith turns up dead, Harry storms into Murphy's house and confronts her at the swimming pool. He chews her out for her all-too-obvious failings. She listens to this while lying on a lounge in the Southern California sunshine, a table full of booze paraphernalia next to her. When Harry's fulguration is finished, she gets uncertainly to her feet, falls against the table and smashes some glass, and we realize for the first time just how drunk she really is. She disses him for his self-righteousness and adds, "Some day I might cry for the little bitch, but when I do you won't be here," and then dismisses him. I can't think of another actress who would have pulled off that scene with such panache.

The same can't be said for the plot. It could (and should) have stayed a first-rate mystery. It's convoluted, sure, but it makes sense at the end. Instead, the writers and the director have bulked it up with "significance." Instead of settling for a well-done genre piece, they've opted for an examination of ontological Angst. What's it all about? There are multiple indications that Harry is overreaching and looking for answers that no one is capable of finding. Now I happen to think that this is a pretty noble quest but nobody else in the movie does. They all discourage him and ridicule him.

Harry demonstrates some tricky knight moves in a chess game to Jennifer Warren and she says, "It's beautiful." I didn't get it. I mean, I get the pun but what does a chess game have to do with the rest of the movie? The movie closes with a visual pun, a wounded Harry in a boat out in the Gulf of Mexico. The boat is beyond his control and is going around in circles. Why? As far as the case is concerned, Harry isn't going around in circles. He's just figured the whole thing out. As far as some banality like "life is pointless" is concerned, the movie hasn't earned the right to lecture us on the subject.

Overall the movie is exceptionally bitter. Except for Harry, there's no one in it who is really straight. It's a bleak view of the society we live in. I guess I don't mind hearing that lecture but I do wish Penn had chosen to resolve the ambiguous ending. Does Harry make it to shore or not? I'd like to know the answer to that. I gave up trying to find the answer to life years ago.

Harry Moseby (Gene Hackman) is a terribly flawed L.A. private detective and former football star. His wife Ellen is having an affair. He gets a case from Arlene Iverson looking for her missing 16 year old daughter Delly Grastner (Melanie Griffith). He discovers that failed actress Arlene needs Delly for her trust fund left to her by her late studio mogul father. Her friend Quentin (James Woods) reluctantly sends Harry to stuntman Marv Ellman. Harry follows the clues to the Florida Keys to her stepfather Tom Iverson and a mother figure in Paula. Harry and Paula are on a boat with Delly diving when she finds a dead man in a crashed plane.

This is a lesser known gem from Hackman in the same era as his classic 'The Conversation'. He brings out another compelling character. There is a murky story but the central story is never lost. There are a couple of future stars including a very young Melanie Griffith. This is a world of murky morality and paranoia of secrets.