In the 1940s, RKO—the weakest of the Big Five throughout its history—stood out among the industry's largest companies for its focus on B pictures. From a latter-day perspective, the most famous of the major studios' Golden Age B units is Val Lewton's horror unit at RKO. Lewton produced such moody, mysterious films as "Cat People" (1942), "I Walked with a Zombie" (1943), and "The Body Snatcher" (1945), directed by Jacques Tourneur, Robert Wise, and others who would become renowned only later in their careers or entirely in retrospect. The movie now widely described as the first classic film noir—"Stranger on the Third Floor" (1940), a 64-minute B—was produced at RKO, which would release many melodramatic thrillers in a similarly stylish vein during the decade. The other major studios also turned out a considerable number of movies now identified as noir during the 1940s. Though many of the best-known film noirs were well-financed productions—the majority of Warner Bros. noirs, for instance, were produced at the studio's A level—most 1940s pictures in the mode were either of the ambiguous programmer type or destined straight for the bottom of the bill. In the decades since, these cheap entertainments, generally dismissed at the time, have become some of the most treasured products of Hollywood's Golden Age among aficionados.