NEW ORLEANS -- Actor Gary Sinise and New Orleans musicians Troy "Trombone Shorty" Andrews and Harry Connick Jr. will lead the parade of the Krewe of Orpheus on the evening of Lundi Gras, the day before Fat Tuesday, and perform at the glitzy ball that follows.

The celebrity riders were announced Thursday at Mardi Gras World, the New Orleans studio where many Carnival floats are built.

Orpheus marks its 20th anniversary when it parades Feb. 11 with more than 30 ornately-decorated floats, some designed to reflect parade themes of the past.

"It's a nostalgic look back at our 20 years," Sonny Borey, the krewe's captain, said during a news conference that included a jazz trio playing Mardi Gras tunes and a local artist painting what will be the commemorative 2013 parade poster.

The Krewe of Orpheus was co-founded in 1993 by Connick and Borey. It has about 1,200 members and is known for attracting celebrities. Those with musical backgrounds often perform at the ball held at the Ernest N. Morial Convention Center after the parade.

Next year, Connick will perform an original song he wrote for the anniversary, called "Smokey Mary Boogie Woogie Choo Choo Train." The song will be on Connick's upcoming album of Carnival music.

Sinise, who stars in the CBS crime drama "CSI: NY," will perform with his Lt. Dan Band -- named after the character he played in the 1994 film "Forrest Gump," which also starred Tom Hanks.

Joining them in the parade will be Emmy and Golden Globe winning actress Mariska Hargitay, who rode in Orpheus in 2012 alongside rocker Bret Michaels and Grammy-winning singer Cyndi Lauper.

The Imagination Movers, a New Orleans-based rock band for kids, and Animal Planet's Tillman, the skateboarding bulldog, will also ride.