Counterattack alleged that Ritt had helped Communist Party-affiliated locals of the New York-based Retail, Wholesale and Department Store Union stage their annual show. Also cited was a show he had directed for Russian War Relief at Madison Square Garden. His associations with the Group Theater, founded on a Russian model, and the Federal Theater Project (which Congress had stopped funding in 1939 because of what some anti-New Deal congressmen claimed to be a left-wing political tone to some productions), were also known to HUAC. He was finally blacklisted by the television industry when a Syracuse grocer charged him with donating money to Communist China in 1951. He supported himself for five years by teaching at the Actors Studio.

In 1952, Ritt was acting, directing, and producing teleplays and television programs when he was caught up by the Red Scare and investigations of communist influence in Hollywood and the movie industry. Although not directly named by the House Un-American Activities Committee (HUAC), Ritt was mentioned in an anti-communist newsletter called Counterattack, published by American Business Consultants, a group formed by three former FBI agents.

Unable to work in the television industry, Ritt returned to the theater for several years. By 1956, the Red Scare had decreased in intensity, and he turned to film directing. His first film as Director was Edge of the City (1957), an important film for Ritt and an opportunity to give voice to his experiences. Based on the story of a union dock worker who faces intimidation by a corrupt boss, the film incorporates many themes that were to influence Ritt over the years: corruption, racism, intimidation of the individual by the group, defense of the individual against government oppression, and most notably, the redeeming quality of mercy and the value of shielding others from evil, even at the cost of sacrificing one's own reputation, career, or life.

Some of the movies he directed include The Long, Hot Summer (1958), The Black Orchid (1958), Paris Blues (1961), Hemingway's Adventures of a Young Man (1962), Hud (1963), The Outrage (1964), The Spy Who Came in from the Cold (1965), Hombre (1967), The Great White Hope (1970), Sounder (1972), Conrack (1974), Norma Rae (1979), Cross Creek (1983), Murphy's Romance (1985), Nuts (1987) and Stanley & Iris (1990).

Ritt's 1964 film The Outrage, is an American retelling of the Kurosawa film Rashomon, and stars Laurence Harvey, Paul Newman, Claire Bloom, Edward G. Robinson, Howard Da Silva, and william Shatner. Like Kurosawa's film, Ritt employs flashbacks in his film. Paul Newman was fond of this role. He traveled to Mexico and spent time speaking to local residents to study the accents. Newman liked that the film's narrative included different points of view.

Ritt and Newman worked together on four other movies, Paris Blues, The Long, Hot Summer, Hud and Hombre. In the 1970s, Ritt won acclaim for movies like The Great White Hope (earning Oscar nominations for James Earl Jones and Jane Alexander), Sounder, Conrack (from Pat Conroy's autobiographical novel), and Norma Rae (Oscar for Sally Field as Best Actress).

In 1976, Ritt made one of the first dramatic feature films about the blacklist, The Front, starring Woody Allen. The Front satirizes the use of 'fronts,' men and women who (either as a personal favor or in exchange for payment) allowed their names to be listed as Writers for scripts actually authored by blacklisted Writers. The film was based on the experiences of, and written by, one of Ritt's closest friends, Screenwriter Walter Bernstein, who was blacklisted for eight years beginning in 1950.

In 1987, Ritt again utilized extensive flashback and nonlinear storytelling techniques in the film Nuts, based on the stage play of the same name, written by Tom Topor. The film was considered a box office disappointment in relation to its budget, although it did not actually lose money.

Ritt died at age 76 in Santa Monica, California on December 8, 1990. The cause of death was heart disease. He was survived by his wife Adele; a daughter, film Producer Martina Wernerand; and a son, Michael.

Ritt moved on from the WPA to the Theater of Arts, then to the Group Theater of New York City. It was at the Group Theater that he met Elia Kazan. Kazan cast Ritt as an understudy to his play Golden Boy. Ritt’s social consciousness and political views continued to mature during his time with the Group Theater, and would influence the social and political viewpoint that he would later express in his films. (Ritt would continue his association with Kazan for well over a decade, later assisting - and sometimes filling in for - his erstwhile mentor at The Actors Studio, eventually becoming one of the Studio's few non-performing life members.)