Total Riff Off is a series of RiffTrax specials that aired on National Geographic Channel as well as NatGeo Wild!. They featured archive footage of previously aired National Geographic material with audio commentary by Michael J. Nelson, Kevin Murphy and Bill Corbett.
The first series originally aired on April 1, 2014 and was repeated once that same evening. A second series aired on December 16, 2014.
All episodes are available as Video-on-Demand releases directly from RiffTrax.