If you notice Darth Vader, flanked by 200 stormtroopers, marching through Pasadena on Monday, don’t worry: You’re not seeing things because you drank too much at a New Year’s Eve party.

“Star Wars” is making its first appearance in the annual Tournament of Roses Parade, and George Lucas is using the opportunity to give something back to his most obsessive fans.

Centerpiece of the “Star Wars” floats — the “Star Wars Spectacular,” as Lucasfilm dubs it — will be 200 members of the 501st Legion, a 3,500-strong group of hardcore fans who appear publicly in full “Star Wars” costume.

The 501st makes public appearances in accurate replica costumes, participating mostly at fund raisers and charity events, always pro bono. Although unaffiliated with Lucasfilm, the company sometimes uses the 501st at its official events.

“When we were releasing ‘Episode III’ around the world, we’d call up the local garrison and ask them to provide some atmosphere and color around the premiere,” said Tom Warner, Lucasfilm’s senior director of marketing. “George was so impressed with these guys — with their dedication and professionalism — he wanted to do something to get recognition for them.”

When Lucas had the idea for a “Star Wars” float in the Rose Parade, an open audition call went out to 501st members. Lucasfilm received 700 videos from costumed fans who filmed themselves marching. These were narrowed down to 200 participants, and Lucasfilm is flying those members in from across the nation and around the world, with 22 countries and 36 states represented.

About 80% will be dressed in the parade as the traditional iconic stormtroopers, with the rest appearing in related costumes such as snowtroopers, sandtroopers and biker scouts, Warner said.

“Think of it as the opening of the Olympics, with each foreign garrison represented by its country’s flag and local garrison arm patches,” Warner said.

Accompanying the 501st will be the Grambling State U. marching band from Louisiana — 176 band members dressed as Imperial officers. Lucas is a big admirer of marching bands, especially Southern show-style bands. They’ll be performing three compositions familiar to fans of the films — the “Main Title,” “Imperial March” and “The Throne Room” — but Warner promises “a New Orleans twist.”

Eight dancers and eight flag girls from Grambling State will also be dressed as Twi’leks — exotic alien dancers from the “Star Wars” films.

Lucasfilm’s “Star Wars Spectacular” will be bookended by two floats representing the theme of this year’s parade, “Our Good Nature.” First float will be the Forest Moon of Endor from 1983’s “Return of the Jedi,” complete with Ewoks swinging between trees. The second float is the planet of Naboo, seen in the prequel trilogy, featuring royal queens, handmaidens, Jedi protectors and even working waterfalls.

Lucas is also the parade’s grand marshal, following in the footsteps of Dwight D. Eisenhower, Richard M. Nixon, John Wayne, Bob Hope, Frank Sinatra, Jimmy Stewart and Mickey Mouse.

Warner insists the decision to name Lucas grand marshal was independent of Lucasfilm’s planned extravaganza. “We didn’t go with that expectation at all. That came after we pitched (the parade organizers) the idea. George is honored and very excited. The 501st was really the genesis of this whole idea.”

One million people are expected to line the parade’s route in Pasadena, with about 30 million watching on TV.

With 2007 marking the 30th anniversary of “Star Wars,” Lucasfilm plans a five-day fan convention at the Los Angeles Convention Center in May.