In a 1998 interview with Cameron Crowe, Billy Wilder, never one to shy away from a reckless statement, took a dismissive stance toward his own work: “There [is] no ‘Wilderesque,’ ” he said. “It’s just … stuff.”

Though as guarded as ever (and at the time, ailing, at 92), Wilder wasn’t completely off base. “Wilderesque” is difficult to define: Is it in the timing? The casting? The writing? It isn’t primarily a matter of formal bravado – though no other filmmaker made Cinemascope look as gloriously lonely as Wilder did in “The Apartment” (1960).

Wilder’s approach was, first and foremost, a matter of attitude, and his dryly comic outlook – by his own admission – derived from that of his mentor, Ernst Lubitsch. Wilder, an Austrian-Jewish emigre, apprenticed himself to old Hollywood pros in the late 1930s and early 1940s. Through Film Forum’s Essential Wilder series, it’s possible to understand Wilder as reacting against – or at least supplementing – the style of his early colleagues.

One example is “Ball of Fire” (July 4). Though written by Wilder and Charles Brackett, the Howard Hawks-directed film is more of a Hawks product than a Wilder movie – in part because Barbara Stanwyck’s slangy dame is less ethereal than a Wilder heroine, and in part because Gary Cooper’s encyclopedia writer is even more of a straightedge than Mr. Deeds. In “Ball of Fire,” Cooper’s character just needs to loosen up a little; typical Wilder protagonists are already too loose.

Lubitsch’s “Ninotchka” (July 11) is a little closer to Wilder-ville, perhaps because it adds a little ethnic flavor in Greta Garbo, playing a Bolshevik on a mission to Paris. In that truly cathartic moment, Garbo laughs, of course – though when Wilder revisited and updated the subject matter in his terrific “One, Two, Three” (1961, July 10), he understood it was funnier if the Russians remained stoic.

Wilder took the “Lubitsch touch” and fermented it: He applied his idol’s nonjudgmentalism to characters who patently deserved to be judged. His heroes are irredeemable – but in the Wilder schema, that is simply a fact of life. It’s always amusing to see how casually Wilder deals with adultery – even in movies where it doesn’t technically occur. In his directorial debut, “The Major and the Minor” (1942, July 4), Ginger Rogers disguises herself as a 12-year-old in order to pay half-fare for a train, and ends up sharing a cabin with and falling for Major Ray Milland. It’s undoubtedly the cutest film ever made with a quasi-pedophilic subtext.

Except in “Double Indemnity” (June 30 and July 1), philandering in a Wilder film is something that just happens – amusingly tolerated rather than frowned upon. (Even in “Indemnity,” the punishment might only be for murder.) The ultimately moralistic “Seven Year Itch” (July 9) starts from the premise that husbands in New York have a season devoted to extramarital sex. It’s paired with the restored version of “Kiss Me, Stupid” (July 9), where Felicia Farr inadvertently swaps places with Polly the Pistol (Kim Novak) and winds up sleeping with Dean Martin to further her husband’s career. In Wilder’s wise and autumnal 1972 “Avanti!” (regrettably not in the series), having a mistress in the end becomes one of life’s pleasures – a sign of wisdom, a recognition of foibles, and a way of letting go.

Conventional Wilder romances, like “Sabrina” (July 19), are never half as fun – and in any event,Wilder’s nice guys always tend to finish last. In “The Apartment” (July 16), Shirley MacLaine’s exhortation to “shut up and deal” may be an admission that Jack Lemmon will always be second to Fred MacMurray for her. (Lemmon, come to think of it, always played second banana: What on earth happens to him after the last line of “Some Like It Hot”?) In “Irma la Douce” (July 17), Lemmon gets with Ms. MacLaine almost from the outset. But since Ms. MacLaine plays the most popular streetwalker in Paris (her “Apartment” coquettishness is thus turned literal), so does everyone else.

Her prostitution is mild compared with that displayed in “Sunset Boulevard” (July 7 & 8) – Joe Gillis is truly Wilder’s greatest whore. Norma Desmond (Gloria Swanson) may be a tragedy of the silent era, but she’s also empathetically crazy – hardly a willing victim in the way that Joe (William Holden) is. Norma’s eyeliner isn’t half as frightening as the moment when Joe rebuffs his writing partner (Nancy Olson): “I’ve got a pretty good deal here,” he says, throwing out love in favor of suits and trinkets. Now that’s Wilderesque.

Most of Wilder’s films, thankfully, remain widely seen, but if there’s a calendar-worthy event in Film Forum’s 22-film series, it’s the July 14-15 run of “Ace in the Hole,” which isn’t officially available on video. Starring Kirk Douglas as “a thousand-dollar-a-day newspaperman” who exploits a mining accident for fame, it’s the rare Wilder film that warrants the label “didactic” – although, according to the biography “Nobody’s Perfect,” Wilder saw even greater callousness in his days as a Viennese journalist. Mr. Douglas is smarmier than ever, and here, marriage proves even less sacred than in most Wilder films when the trapped miner’s wife (Jan Sterling) gets in on the act. “I’ve met a lot of hard-boiled eggs in my life, but you – you’re 20 minutes,” she says to Mr. Douglas. She could have been talking to Wilder himself.

Until July 20 (Film Forum, 209 W. Houston Street, between Varick Street and Sixth Avenue, 212-727-8110).