Complex sentence: The 1981 TV special "The Wave", the 1988 book "The Wave", various stage adaptations, and the 2008 German film "Die Welle" were based on the experiment.
Split into simpler sentences: The 1981 TV special "The Wave", the 1988 book "The Wave" and various stage adaptations were based upon the Wave. The 2008 German film "Die Welle" was also based on the experiment.