For all its action, special effects, and costumes, what would "Star Wars" be without the instantly recognizable music of John Williams? The legendary composer says working with director George Lucas to create the music for the film series has been a journey of its own. As fans line up for the grand finale of the series, “Star Wars: Episode III — Revenge of the Sith,” “Today” national correspondent Jamie Gangel sat down for an exclusive interview with composer John Williams.

Jamie Gangel: This is movie number six for "Star Wars." How do you feel about sequels, and prequels for that matter?

John Williams: Well, it is true that this sixth "Star Wars" is meant to be the last one, if we can believe George Lucas. I sort of took it a step at a time as it came. What's nice now is that I can see because of the way this final story has gone that it all forms a completed circle. I must say I'm getting a big kick out of having survived to be able to do it.

With five Oscars, 18 Grammys and countless other awards, you might think composing these scores comes easily. But Williams, now 73 years old, likes to say it is more perspiration than inspiration.

Gangel: I read you once said you can't have writer's block in Hollywood.

Williams: Working in Hollywood for the orchestra world is a very time consuming and laborious job. People [can] probably not imagine how many notes there are in an orchestral score that can be played in a minute.

Gangel: How many are there?

Williams: Could be thousands, you know. For Star Wars, we recorded 130 minutes of music.

Gangel: You have how long to write that?

Williams: Well, however many weeks we can get in the post-production schedule, usually eight or 10.

Gangel: Wow.

Williams: It's not a lot of time. So, we can stare at the ceiling. But we can't wait for the paint to peel, so to speak.

Gangel: Are there many eureka moments?

Williams: There are occasionally eureka moments — off the top of my head, maybe Darth Vader's theme, you know, the imperial march.

Born in New York, a musical prodigy, Williams loved jazz. But he quickly found himself composing, and over the past five decades has created the mood and tempo for more than 100 movies. His most frequent collaborator? Director Steven Spielberg — they have worked together on some of the country's more popular movies — from "ET" to "Close Encounters" to “Indiana Jones” — and, of course, who can forget “Jaws”?

Gangel: You have ruined ocean swimming for many people, and it's the music not the picture.

Williams: That's very funny about "Jaws." Isn't that amazing, I mean, those couple notes that — that made such an impact.

Gangel: Did you know that music was going to be that scary?

Williams: No, not at all. If you could really manipulate that and do it every time and in every scene and in every film, we'd all be billionaires. And we'd be, you know, geniuses.

Despite all the accomplishments, Williams says one movie overwhelmed him — when Spielberg asked him to score "Schindler's List."

Williams: Spielberg showed me the film … I couldn't speak to him. I was so devastated. Do you remember, the end of the film was the burial scene in Israel — Schindler — it's hard to speak about. I said to Steven, "You need a better composer than I am for this film." He said to me, "I know. But they're all dead!"

Gangel: What's the highest compliment someone could pay you?

Williams: A contributing human being I guess, a contributing musician. If I can contribute something to the vast canon of the great music that's been done over the centuries, [that] would be a nice thing. I'll continue trying.