Justin Timberlake and Amanda Seyfriend sizzled at the Los Angeles premiere of their new film, In Time.

Held at the Regency Village Theater in Westwood, the premiere was also attended by the co-stars Olivia Wilde and Matthew Bomer, along with the film's director, Andrew Niccol (Gattaca, The Truman Show).

In Time is a new sci-fi picture that tells the story of how overpopulation is controlled by how much time is left in each person's life. Time is the most sought after currency, meaning the rich can live for as long as they can afford to.

This is physically the hardest job I've ever done, including world tours . . . I don't even dance. I don't know what I'd call it, Timberlake recently told Collider.

But still, I think it's the thing of, you know, you take a pro athlete: they warm up for an hour, they play a game for three hours, and then they go ice and they're done for a week. And they go next Sunday and they do the same thing. And we're on set for 10 hours, 12 hours and 10 of those some days we're running, he added.

Timberlake, 30, had a special guest with him at Thursday's premiere: his on-again girlfriend, Jessica Biel.

[They] became more and more affectionate, sneaking kisses, whispering to each other, and sharing quick back rubs and caresses . . . at one point, she pretended to punch him a couple times and he gamely bounced up and down like a jack in the box, a source told People.

In Time opens in theaters on Oct. 28. Scroll down for photos from the film's Los Angeles premiere.

Justin Timberlake
Cast member Justin Timberlake poses at the premiere of "In Time" at the Regency Village Theatre in Westwood, California October 20, 2011. The movie opens in the U.S. on October 28. REUTERS
Justin Timberlake, Amanda Seyfried
Cast members Justin Timberlake and Amanda Seyfried other stars of new, sci-fi film “In Time” arrived at the movie's Los Angeles premiere Thursday sizzled in futuristic style at the Regency Village Theatre in Westwood, California. REUTERS
Amanda Seyfried
Amanda Seyfried talks about her role in the upcoming film "Lovelace" REUTERS
Amanda Seyfried
Cast member Amanda Seyfried poses at the premiere of "In Time" at the Regency Village Theatre in Westwood, California October 20, 2011. The movie opens in the U.S. on October 28. REUTERS
Amanda Seyfried
Cast member Amanda Seyfried arrives at the premiere of "In Time" at the Regency Village Theatre in Westwood, California October 20, 2011. The movie opens in the U.S. on October 28. REUTERS
Olivia Wilde
Cast member Olivia Wilde poses at the premiere of "In Time" at the Regency Village Theatre in Westwood, California October 20, 2011. The movie opens in the U.S. on October 28. REUTERS
Matthew Bomer
Cast member Matt Bomer poses at the premiere of "In Time" at the Regency Village Theatre in Westwood, California October 20, 2011. The movie opens in the U.S. on October 28. REUTERS
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