: Velma discovers that Destroido covered up an incident from 20 years ago, which explains why no records existed in the local papers. Production Details Air Date : This episode originally aired in mid-2011.
"The Siren's Song" - Scooby-Doo! Mystery Incorporated (S1E20)
: This episode marks a major turning point in the series’ central mystery. Velma confronts Angel Dynamite , accusing her of being Cassidy Williams , a member of the original Mystery Incorporated who vanished years ago.
: Amy is revealed to be the wife of Dr. Spike Cavenaugh, Destroido’s former chief of geology. She manipulated Velma into helping her rescue her husband, who had been kidnapped by the Fish Freaks.
The gang eventually uncovers a plot by and his group of radical environmentalists. Dressed as "Fish Freaks," they plan to trigger a massive oil spill to destroy the environment as a way to "save it" by proving its vulnerability. Key Revelations