Much of the emotional authenticity is provided by the two leads. Nick Nolte shows both comic grace and passionate depth as "Lucky" Mann (one of Rudolph's verbal plays that doesn't quite come off), a Montreal fix-it man who's estranged from Phyllis (Julie Christie in a career-restoring turn that has justly been accorded best-actress status by at least two critical societies), his ex-B-movie-actress wife. Apparently childless, they have an "arrangement" in which they no longer have sex but Lucky is allowed flings with the lonely, longing women among his clientele. For her part, Phyllis drinks heavily and lolls blearily in bed watching her old horror movies on TV (for an obscure actress with a brief career, her pictures get a surprising amount of air time).

Complementing their more autumnal marriage is that of newlywed Jeffrey Byron III (Jonny Lee Miller, much less charming than he was as Sick Boy in Trainspotting), a fabulously successful, uptight business executive, and Marianne (an estrogen-overdosing Lara Flynn Boyle), his starved-for-affection-and-craving-a-child wife. Invariably introduced in an out-of-focus camera roll that suggests more directorial mannerism than existential bewilderment, Jeffrey is a pissant nihilist indifferent to Marianne's sexual and child-bearing needs. Nietzschean in his aspirations -- his credo is "Leap into the future!" and his faith is in "impossibilities" -- he amuses himself by flirting with a secretary old enough to be his mother and by doing a highwire act across the parapet of his office balcony.

When Marianne, who circles her prime gestation days in red on a calendar, flings herself on Jeffrey and is rudely rebuffed, she announces that she's going to have a child whether her husband is involved or not. In typical but not especially inspired Rudolph fashion, fate intervenes. The lock to the door of their lush condo needs fixing, and on the recommendation of a friend recently satisfied by his service, Marianne gives Lucky a call.

A few double entendres, some phallic tools, and a dip in the pool later, Lucky strikes; meanwhile some Rudolphian sleight-of-hand sets up Jeffrey and Phyllis. The set pieces between the disconnected spouses and their reconfigurations provide the substance of what follows. Fortunately, the older actors make up for the callowness of their junior partners. Nolte toys with the kewpie-doll-like Boyle (her few forays beyond superficiality are a fetish for French and a painting hobby), but his feral panache gives way to a craggy, paternal pathos.

Even more touching and disturbing are the moments between Christie and Miller (Rudolph obviously recognized Christie's primacy in the cast, giving her almost all his best lines). Jeffrey's feckless bravado becomes poignant next to Phyllis's worn, smoky, cozily ironic allure. Reawakened by his attentions, she achieves the true afterglow, surging in sexuality, charisma, and strength, illuminating the pipsqueak lives about her, becoming, in short, the icon that is Julie Christie.

Of course, the film is at its best when Nolte and Christie are together, or hold the screen alone. A scene in a restaurant in which Lucky and Phyllis remonstrate with one another for their failings (one traumatic one in particular) and instinctively nuzzle into tentative reconciliation is subtly heartbreaking. And when each recounts the tragedy of their marriage in separate monologues, it suggests that there might indeed be a conflagration behind this flickering afterglow.

But Rudolph's facetiousness undercuts him throughout; the film's finale is ill-judged slapstick, and seldom has speeded-up photography been used to such self-sabotaging effect. Schematic in plot and erratic in emotional involvement, visually drab for Rudolph and with fewer of his quotable lines ("I don't know what I like but I know what art is" could almost serve as an epitaph for the film), Afterglow nonetheless offers enough brilliance to fuel the hope that Rudolph's spark of genius will burn true again.