Freeman will join the cast in a guest role as Jack starting on February 10. The episode finds the Giant (Jorge Garcia) unleashing his vengeance when a case of mistaken identity leads him to try and settle an old score.
After playing Tess Mercer on Smallville between 2008 and 2011, 30-year-old Freeman has appeared on The Vampire Diaries, CSI: NY and The Playboy Club.
She currently stars in A&E cop drama Longmire, which has been renewed for a second season.
Rena Sofer (Heroes), Lesley Nicol (Downton Abbey) and Rose McGowan (Charmed) all recently signed up for guest roles on Once Upon a Time.