After being forced to drop out of NBC's Parenthood a year ago, due to treatement for breast cancer, Maura Tierney is returning to television.

The actress (who is in remission) will take over one of the lead roles on The Whole Truth, an upcoming ABC drama that tells the story of legal cases each week from the perspective of both the defense and the prosecution.

Joely Richardson was originally signed for the role of District Attorney Kathryn Peale, but dropped out of the project after filming the pilot so she could spend more time with her family. Rob Morrow will also star.

Tierney got her first big break on TV in underrated sitcom Newsradio. She's best-known for her role as Abby on ER.

Check out ABC's first official preview for The Whole Truth (featuring Richardson) right NOW.

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