The half-hour single-camera comedy finds Ryan's character working for her one-time intern after she stayed at home for years to raise her kids.
Ryan's last small-screen starring roles were in the short-lived 1980s shows "One of the Boys" and "Western, Wildside."
Her film credits include the blockbuster romantic comedies "You've Got Mail," "Sleepless in Seattle" and "When Harry Met Sally."
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