Prince has learned a lesson that Madonna should have: Forget about acting and stick to making music. For the most part that's what he does in "Sign o' the Times," a visceral 85-minute concert film of performances last summer in Antwerp, Belgium, and Rotterdam, the Netherlands. Maybe it's just a commercial come-on, but there have been suggestions from the Prince camp that this particular show, built around the songs, themes and energies of his "Sign o' the Times" album, will never tour the United States -- making the film the next-best thing.

What the next-best thing confirms is that more often than not, Prince is one of rock's most charismatic and compelling performers. On songs like "Play in the Sunshine," "The Cross" and the terse title tune, he lays down expansive guitar licks that any spandex-suited behemoth would die for. But rock is just one of the rotors that propel Prince's music and the film, like the album, is full of disparate moods and styles, from the hard-core funk exhilaration of "Housequake" (with a go-go bottom and dollops of James Brown stage moves) to the sweet falsettos and sensuous grooves of "Slow Love" and "If I Was Your Girlfriend" and the rollicking roar of "I Could Never Take the Place of Your Man."

Of course, Prince being Prince, he wasn't satisfied with a mere performance. The set is a frenetic, neon-cluttered realization of the album's "urban junkyard"cover (a bit too heavy on the smoke, though), and at some point Prince must have said "let there be lights," and there were lights. There is also a story line of sorts, advanced by clumsy vignettes that work better conceptually than in reality, in which Prince addresses (and sometimes undresses) the tensions of establishing and maintaining relationships in scenes acted out by the star and several members of his 10-piece band -- most notably Cat, a dancer/singer who seems the embodiment of every salacious lyric he's ever sung.

But pay no attention to the concept or the weird energy sphere that keeps cropping up. It's the performances that count and they are often intense, direct and affecting. Sometimes frenetic and chaotic, they are for the most part well shot and edited, though Prince (who also directed) is not as inventive with camera angles as he is with musical ones. The band, tight as a drum, reflects Prince's authoritarian creative style, looking like plugged-in puppets waiting for someone to turn on the juice. The one exception is Sheila E., freed from her role as sex-kitten vocalist and given a chance to do what she does best and enjoys most -- play the heck out of the drums.

She's a lot more fun to watch than Buddy Miles. But almost all the sexual energy is reserved for Prince, in a series of outfits that would make Cher blush. That energy is less salacious than it has been in the past, though Prince several times toys rather explicitly with Cat -- on "If I Was Your Girlfriend," for example, as well as "Hot Thing" (which it certainly is). Cat, whose presence is felt in practically every song, has a great future in aerobic exercise tapes.

The only sour segments are Prince's duet with Sheena Easton on "U Got the Look" -- which was hot as a video, but with its lip-and-hip syncing, looks out of place in the concert context -- and "Forever in My Life," a gospelly song that simply goes on too long. There's also some obvious cheating in the form of postconcert overdubbing, but maybe that, too, is just a "Sign o' the Times." The film as a whole is a little like one of those inflatable love dolls -- a reasonable facsimile, but nothing like the real thing.

Sign o' the Times, opening today at area theaters, is rated PG-13 and contains a little bump and grind and some dumb sexual lyrics.