"Once Upon a Time" season 4 has officially begun with casting call underway for Anna, Elsa, and possibly Kristoff.

Recently, "Once Upon a Time" season 4 co-creator Adam Horowitz updated fans with photos on Twitter showing the casting call for Anna and Elsa has begun.

The search continues... #OnceUponATime season 4! pic.twitter.com/JN4ZUoVxMc

— Adam Horowitz (@AdamHorowitzLA) June 21, 2014

Casting for #OnceUponATime season 4! Hard at work! Hope to see ya this fall! pic.twitter.com/Zk5TWfAZnx — Adam Horowitz (@AdamHorowitzLA) June 13, 2014

One such hopeful is young Instagram idol Anna Faith, who successfully campaigned to audition for "Once Upon a Time" season 4 by rallying her Instagram followers.

"So yesterday I auditioned for ABC's 'Once Upon A Time.' Thank you all soooooo much for allowing me this opportunity," wrote Faith on Instagram. "I couldn't have made it here without all of this love and support. Thank you all so much! I'm so excited to see what happens now."

Most fans know by now that the characters Elsa, Anna, and Kristoff from "Frozen" will grace "Once Upon a Time" season 4, and recent spoilers confirm that they will appear on different capacities.

TVLine reports that Elsa, being the character shown at the end of "Once Upon a Time" season 3 finale, will appear in the most number of episodes, about nine. Anna, however, will appear from six to eight episodes, and Kristoff will appear in as many as six.

Meanwhile, the 2014 TCA Awards will air on July 19, and "Once Upon a Time's" very own Ginnifer Goodwin has been nominated for her role on the ABC series.

According to Zap2it, "Brooklyn Nine-Nine" actor Terry Crews will host the event.