Sally Pressman has new marching orders.

The Army Wives actress is joining Once Upon a Time‘s fourth season, but mum’s the word on exactly who she will be playing.

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Pressman announced her casting on Twitter late Friday, writing, “There were extensions, eyelashes and gowns…and a very happy actress.” (Once EP Adam Horowitz confirmed the news in an enthusiastic retweet.)

The content of Pressman’s tweet (extensions?!) suggests that she will be playing the dearly departed mother, likely in flashbacks, to Frozen’s lavishly locked sibs Elsa (Georgina Haig) and Anna (Elizabeth Lail), although that has not been officially confirmed.

Once kicks off its fourth season on Sept. 28 at 8/7c.