The French actress Jeanne Moreau (1928-2017) had already appeared in 20 films before “Elevator to the Gallows,” the 1958 thriller directed by Louis Malle, elevated her to stardom. 

Malle had seen Moreau in a Paris stage production of “Cat on a Hot Tin Roof” and was riveted by her turn as the mercurial Maggie. He wasn’t alone in his admiration. “All the young directors of the New Wave,” Moreau recalled later in life, “came to see me.” How could they not? Moreau was, in the estimation of her friend Tennessee Williams, proof of “a God who gets things right.”

After finagling a backstage visit with the actress, Malle begged Moreau to take on the role of Florence Carala, the adulterous wife of a munitions maker in “Gallows.” You don’t need to know that Malle would soon have an affair with Moreau: His adoration is there to see in the opening frames of the picture. Moreau’s avowals of love are all but beside the point; focus, instead, on the intimate-bordering-on-invasive proximity of Malle’s camera.

“Elevator to the Gallows” is featured in “Jeanne Moreau, Actrice,” a two-week retrospective of 19 films beginning on March 3 at Film Forum. Malle’s picture is getting a large share of the showings, edging out art house mainstays like “Jules and Jim,” “La Notte,” and “The Lovers,” the director’s follow-up to “Gallows.” It’s not hard to intuit why: Between the blatant adulation of Moreau, the smoky Miles Davis soundtrack, and its noir-ish trappings, Malle’s picture has more existentialist angst than any one generation can fully absorb.

Moreau was one of two daughters born to restauranteur Anatole Moreau and Kathleen Buckley, a dancer in the Folies Bergère who worked alongside Josephine Baker. Moreau was drawn to acting upon seeing a production of “Antigone” as a teenager. Notwithstanding her father’s disapproval — Monsieur Moreau threw young Jeanne out of the house after coming upon her picture in a trade publication — Moreau joined the Comédie-Française and, later, the Théâtre National Populaire.

The list of directors who sought Moreau’s talents is a who’s-who of mid-20th century auteurs, including François Truffaut, Luis Buñuel, Michelangelo Antonioni, Joseph Losey, Jacques Demy, Rainer Werner Fassbinder, and, four times over, Orson Welles. 

Admittedly, “The Deep” was never completed, but Welles’s inclusion of Moreau in “The Trial,” “Chimes at Midnight,” and “The Immortal Story” — each of which will be screened at Film Forum — testifies to his estimation that she was “the greatest actress in the world.”

Welles was fond of hyperbole, but his praise rings true when considering Moreau’s turn as Catherine in “Jules and Jim” (1962). Truffaut’s rambling account of friendship, love, and its sundry complications remains startlingly fresh. The opening moments, with their fractured editing and compacted elisions, are a case study in breathless exposition. Only “A Hard Day’s Night” captures the irrepressible headiness of youth with as much cinematic élan. 

Still, its title notwithstanding, the hub of “Jules and Jim” is Catherine. The march of time confers inevitability on all things, so Moreau’s casting seems predestined, but, really, could this film have been anywhere near as indelible without this one particular actress? On paper, Catherine is an annoying hodgepodge of plot contrivances; in Moreau’s hands, she’s a force of nature with all the terrifying independence that suggests.

Welles’s greatest actress was also a director. Following on the heels of “Jeanne Moreau, Actrice,” Film Forum will be presenting “Jeanne Moreau, Cinéaste,” featuring restorations of “Lumiere” (1976), “The Adolescent” (1979), and “Lillian Gish” (1984). 

The latter documentary will be accompanied by select screenings of Gish films like Victor Sjostrom’s “The Scarlet Letter” (1926) and “The Wind” (1928) — both with live piano accompaniment — as well as “Night of the Hunter” (1995), Charles Laughton’s lightning strike of a masterpiece. Moreau’s homage bears watching not least for the opportunity to watch the First Lady of American Cinema in conversation with one of her most indelible progeny.