“Magnolia” begins with a narrator telling us about some amazing coincidences — like a guy who lived at Greenberry Hill being killed by three guys named Green, Berry and Hill — and then telling us that “these things just happen. It’s just something that happens.”

Now we’re expecting a movie in which widely variant characters’ lives somehow intersect each other at random moments, causing coincidences that change everyone’s direction. We’re excited; we like movies with cool intersecting plots like that.

Unfortunately, only a few of the stories really do intersect. There are about a million stories going on at once, and only two things connect them all: One, a weird natural occurrence that affects all of Los Angeles, where this takes place (for a hint, read Exodus 8:2, which is referenced no fewer than four times in the film); two, a fascinating sequence in which all of the major characters sing along with the song currently playing on the soundtrack (a very cool film device, and an effective one here, not just for being quirky, but for expressing emotion).

The main stories: An old guy named Earl (Jason Robards) is dying of cancer. His estranged son, Frank (Tom Cruise), is now an offensively crass infomercial guy whose system, “Seduce and Destroy,” teaches men how to have sex with any woman they choose. Earl wants to see Frank. Meanwhile, Earl’s trophy wife Linda (Julianne Moore) has actually fallen in love with the rich old guy and bear to see him die.

Meanwhile, whiz-kid Stanley (Jeremy Blackman) is a contestant on the long-running live-TV game show “What Do Kids Know,” hosted by Jimmy Gator (Philip Baker Hall), who also has just found out he has cancer, and who also has an estranged child, a cocaine-addicted daughter named Claudia (Melora Walters), with whom a good-hearted cop named Jim (John C. Reilly) starts to fall in love.

Stanley, a true genius, hates being forced into this by his father. All-too-familiar with the situation is grown-up former-whiz-kid Donnie Smith (William H. Macy), who now moons over cute male bartenders and says he has lots of love to give, but nowhere to put it (an important idea in this film).

All of these stories add up to the same themes of forgiveness and regret. “We may be through with the past, but the past isn’t through with us,” we’re told a couple times. Despite our changed ways and good intentions, the regretful things we may have done before can still come back to haunt us.

That’s all well and good, but did we need to see a dozen different stories that all say the same thing? Any one of these subplots could have been developed into its own story and express the point just about as powerfully.

If writer/director P.T. Anderson wanted to explore coincidence and chance in our daily lives, he had a perfect opportunity to do it here. But coincidence and chance don’t play nearly as big a part in this film as we’re led to believe they will. Instead, we’re mainly just seeing a bunch of stories acted out before us, all of which have the same moral.

To his credit, Anderson has assembled a fantastic cast — probably the best cast of any film in the last year — and pulled excellent performances from everyone. Pretty-boy Cruise, in particular, has never given more of himself to a role than this one, pulling tears from the audience as he struggles to maintain his offensive facade.

Robards and Hall are also exemplary in their roles as old men who wish they’d done things differently. And Macy is nearly heartbreaking as the man who feels he has no place in life anymore.

Does the film NEED to be three hours long? It’s a moot point. It would be impossible to tell all these stories in less time; the question is, do ALL these stories need to be told? I say no, although I was honestly interested in each of them. I just wish they’d all added up to more, and that “Magnolia” itself had meant more than it did.

B (; R, abundant harsh profanity, very crude sexual dialogue and sexual situations.)