The Strange Case of Dr. Jackel and Mr. Snyde/Stone Statue Mayhem

Plot Summary
Everything seems perfectly fine at the Plumbers' Headquarters, 'til Dr. Jackel (portrayed by Ben Stiller in this episode, shows up, and eventually transforms from himself to Mr. Snyde.

Cartoon Episode:
Stone Statue Mayhem

Transcript
The Strange Case of Dr. Jackel and Mr. Snyde transcript