Season 1, City on the Edge of Forever, Episode 28.

Mr. Sulu's time warp shocks the Enterprise. Dr. McCoy was treating him when the ship rocked, causing him to accidentally inject himself with a dangerous drug. Temporarily insane, McCoy fires his beam at the orbiting planet.

Kirk leads a landing party to Earth, where they discover a monolith that can transport someone to any time in history. After Kirk and Spock digested this surprising discovery, McCoy jumped into the machine.

Suddenly, the company disappeared. They realize that McCoy must have changed history to prevent their existence. Kirk and Spock travel through time to find and prevent McCoy from reaching New York City during the Great Depression.

They need food and shelter, and a kind and selfless woman assists them in their mission to serve the city's large homeless population. Edith Keeler.

Edith is an optimist who believes that humanity can prevail and that better times have come. Kirk, who was usually only attracted to legs or cleavage, did notice her beauty, but more so for her insight and enthusiasm. Feminine captains are rare!

Usually Spock will study McCoy, while Kirk will fall in love with Edith. They soon realized what was happening to their future.

Edith initially dies in a traffic accident, but McCoy saves her. Edith would later become the leader of the global pacifist movement that delayed the United States' entry into World War II, allowing Germany to win and change the history of the planet forever.

Just as they find McCoy, Edith steps into traffic, and a distressed Kirk prevents McCoy from saving her. This episode is the best of Trek. Sacrifice, duty and honor. It also humanizes jet lag travel, which is often used as a plotting device.

It's worth mentioning that this episode is on almost every list of the best Trek episodes of all time.

Of course, this episode is far from perfect. The original script by sci-fi legend Harlan Ellison won an award but was ruined by this episode. In the original script, instead of the time-traveling McCoy, there was a crew member suffering from drug dependence and overdose. Ellison wanted to address the complexities of substance abuse and point out that it's a real human problem, even in the idyllic Star Trek world.

This is inconsistent with creator Gene Roddenberry’s vision for the future, and will never transcend contemporary online censors. During the taming process, the final version, edited by legendary writers Robert Bloch and DC Fontana, is still fresh in my memory.

Trivia bits, buildings and roads used to simulate depression in New York, were used in many productions. Part of it was built for Gone with the Wind - the Atlanta scene that can also be seen in Adam 12 and The Twilight Zone. The best time was as Mayberry on the long running Andy Griffith Show and Mayberry RFD.

Fans of The Andy Griffith Show fondly remember Floyd, the addictive but lovable barber who ran Mayberry Barber Shop. Floyd the Barber).

This store can be seen in City on the Edge of Forever This show is an absolute standout!