The fourth season of The New Adventures of Old Christine premiered on CBS on Wednesday nights at 8:00pm on September 24, 2008 and concluded on May 20, 2009. It consisted of 22 episodes.
In this season, Barb, who is divorced, faces deportation from the U.S. To help her, Christine decides to enter into a sham lesbian marriage with Barb to keep her best friend in the country. Meanwhile, Richard and New Christine become engaged, and Matthew finds love with one of his clients. Christine briefly dates an obsessive man named Patrick. Additionally, Christine and Barb convert their gym into a spa, only to discover it has unexpectedly become a brothel. On the day of Richard and New Christine's wedding, Christine briefly reconciles with New Christine's father but is later heartbroken to learn he is engaged to someone else. This leads Richard to rush to Christine's side, leaving New Christine angry and jealous, and ultimately causing her to leave him at the altar. Meanwhile, Barb and Christine's sham marriage is discovered by an INS officer, resulting in Barb's imprisonment.
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