The Showtime comedy focuses on a British couple whose television programme is remade into a bad American series.
The Hollywood Reporter says that Griffiths will play a version of himself on the show. His character will be thought "too sophisticated" to star in the American remake and will be replaced by LeBlanc.
Producers of the series were recently forced to recast some parts as Thomas Haden Church and Claire Forlani decided to quit the project.
Episodes is currently in production.