They proceed to the Vulcan temple, which is based on the only original series episode to visit Vulcan, "Amok Time." also involving a ceremony. Theodore Sturgeon, the famed science fiction writer and author of that episode, had the idea that an advanced society like the Vulcans would preserve primal elements of their pre-technological traditions.

The art department worked Vulcan symbols into styling a place that otherwise looks vaguely Tibetan crossed with Chinese, with a little suggestion of the Flash Gordon tradition of depicting aliens as Asians, like the Emperor Ming. And the long-legged female attendants in diaphanous white gowns adds a bit of Cecil B. Demille's Hollywood Babylon sex appeal to the exotic situation. But the scenes here work, thanks to excellent dialogue, Nimoy's camera work and the montage editing, and of course, to the authority of Dame Judith Evans as the Vulcan High Priestess, T'Lar.

This was Nimoy's casting coup, but he got this living legend of the British and American stage because her nephew was a Star Trek fan. She contributed more than just her performance. According to Harve Bennett, it was her suggestion that her lines include a reference to the danger to McCoy of the "re-fusion" ritual. It would set up a memorable moment.

Though this is a story about Spock, and is Nimoy's directorial debut, and it features a strong performance by William Shatner and memorable scenes for the other cast members, I always think of "Star Trek III" as DeForrest Kelly's movie. He is central to its plot, and he has some of the best scenes and best lines in the film. In his comic scene in the bar where he's trying to hire transport to Genesis before the Enterprise crew gets involved, his Vulcan and McCoy personalities clash, sometimes in a single line, ending with his desperately futile attempt at a Vulcan neck pinch. Then his line when Kirk tells him he's the victim of Spock's mind meld: "This is his revenge for all those arguments he lost." His line on the Genesis planet in response to Kirk's dismay after destroying the Enterprise, his dramatic confession of affection to Spock's inert body, and then his quintessential response to T'Lar.

Dame Judith tells McCoy that the danger to him is as great as it is to Spock, and he must choose whether or not to go through with the ritual. Looking simultaneously uncomfortable and resolute, McCoy says clearly, "I choose the danger."

I choose the danger! Actors wait their entire careers for a line like that. But Kelley follows it immediately with an acerbic aside: "Hell of a time to ask." In just two perfectly delivered sentences, DeForest Kelley defines the Leonard McCoy character perfectly and delightfully. Kelley himself once said that the secret of Trek films was in the moments. This is a great Star Trek movie moment.

This section of the film is a textbook of graceful efficiency: the close-ups, the two and three shots of the approaching characters, their lines and responses, the montage of the waiting, and then another signature exchange between Kirk and Sarek, before the final moments of Spock struggling to recover his memory and understand what has happened.

In one of Mark Lenard's best Trek movie moments, Sarek looks at Kirk with an expression of suppressed gratitude and pain. "Kirk, I thank you. What you have done---"

"What I have done I had to do."

"But at what cost?" The pain is in the cadence, rather than the still-logical tone of voice. "Your ship, your son---"

"If I hadn't tried, the cost would have been my soul."

The quest to re-integrate Spock by restoring his soul was demanded of Kirk's integrity, his soul. When Nimoy's innocent, puzzled Spock in the hooded white robe asks Kirk why he came back for him, Kirk eventually reverses the ethical pronouncement at the heart of the previous movie by saying: "Because the needs of the one outweighed the needs of the many." In this context it isn't a contradiction, but a completion. Both sides of the proposition are true, or can be.

How can this be? Kirk hints at how it works in a line just previous to this one, which Shatner says almost as a throwaway, when he tells Spock, "You would have done the same for me."

This is the heart of our day- to-day ethical relationships, the essence of how and why human societies work, combining empathy and reciprocity, and enabling both acts of great courage and cost, and ordinary courtesies: you'd do the same for me.

The circle of friendship is joined when the Enterprise crew gathers around Spock, reunited with their friend, himself recently "reunited." Though this is one of the few Star Trek films that doesn't end with the Enterprise heading off on its next mission, the sense that there will be more Star Trek movies precedes the words flashing onto the screen as this picture ends (with perhaps a nod to Gene Roddenberry and his ending for Star Trek I): "...and the adventure continues."