Let the Hunger Games begin! "The Hunger Games: Catching Fire," the second installment of the best- selling young adult book series, has yet to hit theaters, but the films' stars are already hard at work on the next movie.

According to a report from E! Online Monday, actors Jennifer Lawrence and Liam Hemsworth were spotted on "The Hunger Games: Mockingjay - Part 1" set in Atlanta over the weekend. While Lawrence wasn't photographed wearing her character Katniss Everdeen's post-apocalyptic attire, she was spotted sporting an unusual accessory- an arm cast. Hemsworth, who is reprising his role as Everdeen's friend and sometime love interest Gale Hawthorne, was reportedly seen in full hair and makeup on the set.

While Josh Hutcherson is again playing fellow "Hunger Games" contestant survivor Peeta Mellark, he wasn't seen on set, but a newcomer, Oscar-nominated actress Julianne Moore, did make an appearance. In photos obtained by E! Online, the normally red-headed actress can be seen sporting grey locks and matching grey-colored contacts. It was first announced by Deadline earlier this month that Moore would portray President Alma Coin in "Mockingjay," a political leader described as being "ruthless" and "hungry for power."

According to "The Hunger Games: Mockingjay - Part 1" IMDB page, the third installment will follow the third novel's storyline closely as Everdeen (Lawrence) stars as the symbol of rebellion for citizens of the post-apocalyptic world of Panem who are fighting their corrupt government, the Capitol. The film is currently scheduled for a Nov. 21, 2014, release.

The second installment in the series, "The Hunger Games: Catching Fire," recently made headlines when analysts predicted that it will gross record-breaking numbers. According to a report from Zimbio, "Cathing Fire" is expected to make $950 million worldwide at the box office, a large jump from the first film "The Hunger Games," which grossed a total of $691 million worldwide in 2012. "Catching Fire" is set to hit theaters on Nov. 22.