|Life on Mars/Ashes to Ashes|
|The Dark Side of the Mook|
|Air Date||February 4th, 2009|
|Written by|| Bryan Oh|
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The eighth episode of the US science fiction crime drama, Life on Mars known as The Dark Side of the Mook was first broadcast on 4 February 2009 produced by 20th Century Fox Television and ABC Studios for ABC.
A mysterious phone call from a tipster leads Det. Sam Tyler to a headless body. A severed head is delivered to the precinct at the same time, thus leading to the discovery of a series of gruesome decapitations that might involve Det. Carling's brother, Eddie. The detectives are interviewed by someone tied to Aries Project.
- This is the first episode to be completely original to the US series.
- This episode was originally broadcast after the following episode.