Star Trek's Best One-Off Guest Star Appeared 58 Years Ago, And The Franchise Still Hasn't Topped Them

One episode of Star Trek: The Original Series is universally regarded as the greatest of them all, and its guest star remains Star Trek's gold standard. 1960s Star Trek may have peaked early with season 1, episode 28, "The City on the Edge of Forever." The penultimate episode of Star Trek season 1 was an epic time travel saga and a doomed romance for Captain James T. Kirk (William Shatner).

In Star Trek: The Original Series' "The City on the Edge of Forever," Captain Kirk and Mr. Spock (Leonard Nimoy) time travel to 1930s New York City to stop a temporarily crazed Dr. Leonard McCoy (DeForest Kelley) from changing the timeline. In Depression-Era New York City, Kirk falls in love with Sister Edith Keeler (Joan Collins), a social worker who proves to be pivotal to Star Trek's timeline. In short, Edith Keeler has to die for history to unfold as it should, and Kirk must make the ultimate, tragic choice between love and the fate of the universe.

Joan Collins As Edith Keeler Is Still Star Trek's Best One-Off Guest Star

Captain Kirk's Great Love Looms Over All Others

Throughout Star Trek's nearly 60-year history of TV shows and movies, countless actors of the highest caliber have guest-starred, but Joan Collins remains in a rarified air. As Sister Edith Keeler, Collins is almost an ethereal presence juxtaposed against the poverty and desperation of Depression-era New York. Keeler is compassionate, intelligent, and believes in a progressive vision of the future, but doesn't suffer fools gladly. It's no wonder Captain Kirk fell for Edith.

Joan Collins went on to become a TV legend who is best known as the seductive Alexis Carrington on the prime-time soap opera Dynasty. In Star Trek, Collins embodied grace, hope, and light as Sister Edith Keeler. Even though she only appears in one episode of Star Trek: The Original Series and is never referenced again, Joan Collins made Edith Keeler unforgettable. Within Star Trek canon, Edith Keeler's tragic fate literally enabled Gene Roddenberry's optimistic vision of Star Trek's future to be.

Joan Collins Helped To Make "The City On The Edge Of Forever" A Star Trek Classic

Sister Edith Keeler Is Unforgettable

Joan Collins' contribution to "The City on the Edge of Forever" becoming known as the greatest Star Trek: The Original Series episode (and arguably the greatest Star Trek episode, period) can't be overstated. At its core, "The City on the Edge of Forever" is a love story. Collins had to embody Edith Keeler to be someone Captain Kirk would be willing to trade the future for. Kirk, who was devoted to the Starship Enterprise, seriously weighed the fate of the timeline against his love for Edith.

Captain Kirk had many love interests throughout Star Trek: The Original Series, but Edith Keeler shines as Jim's great, doomed love. "The City on the Edge of Forever" may center on time travel, but writer Harlan Ellison's original story (which was altered for broadcast) eschewed many of Star Trek's usual tropes. This only made "The City on the Edge of Forever" stand out, making it more memorable. And, at the heart of Star Trek's greatest episode remains Joan Collins, its greatest guest star.