Mr. Krabs' secret laboratory is a room that is located under the Krusty Krab. It appears in the episode "Krabby Patty Creature Feature."
It is a large laboratory containing a lot of machinery and equipment. Since it is dark inside the laboratory, most of the machinery has a green glow to create light so people can see.
Role in episode
It appears when the customers at the Krusty Krab grow tired of eating the same old Krabby Patty, so Mr. Krabs brings SpongeBob to a secret, underground laboratory and makes a new formula for the patty to attract customers with the help of Sandy, thus inventing the Secret Patty.