The pair will be showing up in the 13th episode of the current season, which will air in the US next year, according to Variety.
Jonathan Whitesell and Kacey Rohl have signed up to play the characters.
Rohl will be known to "Hannibal" fans as Abigail Hobbs. She also recurred in AMC's "The Killing". Whitesell is still new to TV, but guest starred in an episode of The CW's "iZombie" earlier this year.
Bailee Madison has also been confirmed to return as a young Snow White.
Cruella de Vil will also be back for "multiple episodes" later in the season.