Her first episode is to air in February.
"She will play Maxine Denver, a strong and successful Chicago professional who is forced to put her skepticism of 'amateur detectives' aside when The Forgotten Network begins investigating a case close to home," the network said in a release.
The show stars Christian Slater, Michelle Borth, Heather Stephens, Bob Stephenson, Anthony Carrigan and Rochelle Aytes.
Cuthbert is best known for her roles in the movies "Old School," "The Girl Next Door" and "Love Actually," as well as in TV's "24."
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