Dana Wynter, a leading lady who acted opposite some of Hollywood’s biggest names in the 1950s but won enduring fame as the imperiled heroine of a low-budget science-fiction film about aggressive pod people, “Invasion of the Body Snatchers,” died May 5 of congestive heart failure at a hospital in Ojai, Calif., according to the Los Angeles Times. She was 79.

Dana Wynter earned countless fans and a place in film history with her efforts to fend off pod people in “Body Snatchers.”

She landed one of her first lead Hollywood roles in “Body Snatchers,” a B-movie thriller that became an unexpected classic and an enduring popular and critical success. Expertly directed by Don Siegel, the 1956 film was hailed for its ability to create suspense and horror with a well-written script, excellent acting and almost no expensive special effects.

Ms. Wynter played Becky Driscoll, an enchanting divorcee whose sweetheart – Dr. Miles Bennell, portrayed by Kevin McCarthy – discovers a horrifying fact: Their neighbors are being taken over in their sleep by unfeeling alien clones hatched from plant-like pods.

The handsome couple makes a valiant effort to escape the pod people. “I don’t want to live in a world without love or grief or beauty,” Ms. Wynter says when a cloned neighbor advises her to give in and become one of them. “I’d rather die.”

In her exhaustion, Ms. Wynter’s character soon makes the mistake of falling asleep – thus falling prey to the invasion and leaving her boyfriend to fend for himself in an increasingly inhospitable world.

Released in the shadow of the McCarthy-era Hollywood blacklists, the film has been widely described and dissected as a metaphor for anti-communist paranoia and unthinking conformism.

In 1994, the Library of Congress elected to preserve the movie in the U.S. National Film Registry. Ms. Wynter said the film was, at its heart, a plain great yarn.

“One man was writing his thesis on ‘Invasion of the Body Snatchers’ for his degree,” she once told an interviewer. “ He measured — he measured! — the distance from one corner to the other in the town where we shot. ... I thought to myself, ‘These people are out of their minds!’ ”

“Body Snatchers” helped Ms. Wynter win a 1956 Golden Globe for “most promising newcomer,” an award she shared with Anita Ekberg.

In the ensuing decades, she played mostly decorative roles, appearing as a beguiling brunette in dramas such “D-Day the Sixth of June” (1956) with Robert Taylor and “Something of Value,” a 1957 film about the Mau Mau uprisings in Kenya with Rock Hudson and Sidney Poitier.

She played Kenneth More’s assistant in the World War II movie “Sink the Bismarck!” (1960) and starred with George C. Scott in “The List of Adrian Messenger” (1963), a detective mystery directed by John Huston with cameos by a raft of big-name actors, including Tony Curtis, Burt Lancaster and Frank Sinatra.

In 1970, Ms. Wynter appeared as Lancaster’s wife in “Airport,” but her film career mostly trailed off after she married and had a son. She continued to appear regularly on television into the 1980s. She co-starred with Robert Lansing in the 1960s series “The Man Who Never Was” and acted in series including “Wagon Train,” “The Love Boat,” “Magnum, P.I.,” and “Cannon.”

She most enjoyed acting live on television, she once told an interviewer, as she did for several years in the late 1950s on the program “Playhouse 90.”

“I can’t begin to describe the adrenaline rush, the excitement. Because there was jeopardy,” she said. “If anything went wrong, there were all those people looking in.”

In interviews, “Body Snatchers” director Siegel often claimed to have frightened Ms. Wynter by breaking into her house and putting a pod — fresh from the movie set — under her bed.

Not so, Ms. Wynter told Tom Weaver for his 2001 book of interviews, “I Was a Monster Movie Maker.” Siegel left the pod on her doorstep, and Ms. Wynter encountered it — “I nearly broke my neck!” she said — while leaving her cottage early the next morning.

A full obituary will follow.

This post has been updated to reflect that “Body Snatchers” was one of Ms. Wynter’s first leading roles in the United States — not the first.