AceShowbiz -

More "Frozen (2013)" characters are coming to "Once Upon a Time". In addition to The Snow Queen a.k.a. Elsa who was introduced in a teaser for season 4, Anna and Kristoff will reportedly be also featured in the next installment of the fantasy drama series.

According to TVLine, casting in now underway for the Snow Queen, her sister Anna and ice merchant Kristoff. Elsa is said to appear in approximately nine episodes, while the other two characters will appear in less episodes. The show's bosses said "no comment" when asked if a CGI Olaf would also show up on the ABC series.

Elsa, the Queen of Arendelle who is in her late-20s/early-30s, was voiced by Idina Menzel in the Disney film. Kristen Bell lent her voice for Elsa's sister Anna, who is described as "a fun-loving, fearless optimist who often gets herself into situations where she is in over her head, yet is able to triumph due to her resourcefulness and can-do spirit."

As for Kristoff, who by the end of the film has grown romantic feelings for Anna, was voiced by Jonathan Groff in the big-screen version. When he first appears on "Once", "he is adjusting to life at the castle - including sleeping indoors for the first time in his life."