The pilot of “Cagney & Lacey” starred Loretta Swit as Cagney. Due to her contract limitations on “MASH” she was unable to continue the role when “Cagney & Lacey” was picked up as a series. Ms. Swit was replaced by Meg Foster. She was apparently viewed as being too aggressive and because of that and other reasons, was replaced by Sharon Gless. Even Lacey’s husband was played by a different actor in the pilot. Lastly, the fantastic theme song (one of my all time favorites!) was different in the pilot.
IMHO, all the changes made from the pilot were good ones and what made the series so great.
Here’s the 2 hour plus pilot.