The girl in “The Girl Can’t Help It” is Jayne Mansfield, and the thing she can’t help — or rather the biggest of the many things she can’t help — is the spectacular effect of her monumental bosom. Sheathed in Technicolor sequins, they propel her forward like a pair of megaton rockets in perpetual detonation. Blocks of ice melt in their wake, eyeglasses shatter, and bottles of milk erupt in the clutch of flabbergasted gentlemen, their white-hot geysers an outrageous innuendo.

The dynamism of these preternatural appendages is managed by a complex set of balances: a seesaw swing of the hips, feet put forward in a concentrated prance, arms propped up like some bodacious praying mantis. She’s as tricked out as a Cadillac El Dorado, as synthetic as Jessica Rabbit. Of the 743 gags that director Frank Tashlin claimed (in a letter to Jean-Luc Godard) to have worked into the film, the best stem from Mansfield’s anatomy.

“The Girl Can’t Help It” celebrates its 50th anniversary this week at Film Forum (a weeklong Tashlin retrospective begins next Friday with “Will Success Spoil Rock Hunter?”) in a new 35 mm print that clarifies its every tacky detail. The premise is magnificent nonsense. Repugnant ex-con Marty “Fatso” Murdock (Edmond O’Brien) hires alcoholic publicist Tom Miller (Tom Ewell) to make a star out of his tone-deaf fianceé, Jerri Jordan (Mansfield), whose only ambition is to slave away in some fabulously appointed kitchen for the pleasure of a grateful husband, preferably not Fatso. High decibel farce ensues as Tom and Jerri tour the club circuit, cut a record, and fall in love, while Marty sweats out fits of envy and generalized hysteria.

All of this serves as a pretext for puns, gimmicks, rapid-fire slapstick, giddy rock numbers (courtesy of Little Richard, the Platters, Fats Domino, and half a dozen others), and the flaunting of spectacularly garish production design. Tashlin mounts his chintzy fantasia with palpable zest and mischievous ambivalence.The girl can’t help it, and neither can he; the film obliterates the line between celebration and satire.

From the minute he was championed by Mr. Godard, Truffaut, and the rest of the Cahiers du Cinema set, Tashlin maintained something of a cult reputation. His formal chops were clear as day; the most delirious antics in “The Girl Can’t Help It” are leveled by a classical eye for composition and a steady hand in the cutting room. But his lasting influence has less to do with the rigors of mise-en-scène than his supremacy in evoking what Philip Roth dubbed “the indigenous American berserk.”

The pure products of America have never gone crazier than they do in Tashlin. He rivals Douglas Sirk as the quintessential Atomic Age auteur. And just as Sirkian melodrama has inspired generations of cerebral ironists (Fassbinder, Todd Haynes, Joao Rodrigues), so has Tashlin’s radioactive excess stimulated its own tradition.

The brash satires of Joe Dante, Tim Burton, McG, Paul Verhoeven, and the Coen Brothers are indebted to his cartoon aesthetic. More unexpectedly, DNA from “The Girl Can’t Help It” mutates throughout the David Lynch oeuvre. The nightclub numbers in “Blue Velvet” mimic the hallucinatory chromatism of Abbey Lincoln’s “Spread the Word” routine. “Wild at Heart,” that Tashlinesque fantasy, quotes “Be-Bop-a-Lula.” And the creepy sock hop credit sequence from “Mulholland Drive” is a direct reflection of Tashlin’s point of departure.

So Godard’s prophecy has come true: “In fifteen years’ time,” he wrote in 1957, “people will realize that ‘The Girl Can’t Help It’ served then — today that is — as a fountain of youth from which the cinema now — in the future, that it — has drawn fresh inspiration.”

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