Bassie & Adriaan: The Crying Professor S01 E08 Episode 8

Professor Archibald Chagrijn exposes the world to his blubbering gas, which makes people sad and causes them to cry. Bassie proves immune to the blubbering gas -- as he has had an overdose of laughing gas. The professor is hiding on the Canary Islands, but Bassie and Adriaan manage to track him down.