David E. Kelley, the man behind such landmark television programs as “Chicago Hope,” “Ally McBeal,” “The Practice,” “Boston Legal” and countless more may jump ship on his U.S. adaptation of the BBC SF cop series “Life on Mars” for ABC.

If Kelley does depart as showrunner, ABC has decided to continue with the project without him and will team up with 20th Century Fox TV to make the series happen with new producers Josh Appelbaum, Andre Nemec and Scott Rosenberg.

The show centers around a 21st Century police detective who is transported back in time to the 1970’s after an automobile accident. It is never made clear if what he is experiencing is real or just his imagings during a coma state. While in the past by 30 years, he encounters a serial killer that may be responsible for his girlfriend’s disappearance in the future.

Jason O’Mara will play the lead role made popular in the British series by John Simm. Joining O’Mara are “Star Trek: DS9″ alum Colm Meaney, Rachelle Lefevre and Lenny Clarke (”Rescue Me”).

Of course, since Kelley was hot for this series and was the main thrust behind the American adaptation the big question is why, now that the pilot is shot and the show is in post-production would he leave? Kelley is known for sticking with a project and seeing it through. According to Variety the biggest issue for Kelley may be purely a financial one and one of ultimate control.

Stay posted to Slice of SciFi for any updates on this story.