He is a giant, transparent, brown, dirty bubble, hence his name. He has black eyebrows and pupils. His eyes go above his head when surprised. He can capture an object by landing over it and sucking it in.
Powers and abilities
Being a bubble, the Dirty Bubble has the ability to float and fly in the air. He can also trap his enemies inside of his body with his "awesome surface tension."
Being a bubble, pointy objects are the Dirty Bubble's sole weakness, as they will simply pop him. He freaks out when near them.
Role in series
"Mermaid Man and Barnacle Boy II"
The Dirty Bubble suddenly appears and attacks Mermaid Man and Barnacle Boy, trapping them inside of him. When SpongeBob emerges from the diner, having found the The Adventures of Mermaid Man and Barnacle Boy theme song on the jukebox, he defeats the Dirty Bubble by popping him with a pencil, which he claims was for him to sign his autograph with.
The Dirty Bubble returns, alongside Man Ray, in this episode. Man Ray has teamed up with him to form an organization called E.V.I.L. (Every Villain Is Lemons). When Barnacle Boy tires of Mermaid Man treating him like a young child, he joins the two and commits crimes. However, in the end, Barnacle Boy returns to the good side, leaving Man Ray and the Dirty Bubble disappointed.
In the lost episode of Mermaid Man and Barnacle Boy, the eponymous heroes are spying on the Dirty Bubble. He is taking a bus to Bikini Bottom. The two heroes decide to stop whatever evil he is doing. Then, the scene cuts to the Dirty Bubble coming out of the bus, laughing, and Mermaid Man and Barnacle Boy watching.
Outside of "Motel Evil," the Dirty Bubble shoots Man Ray out of his mouth and fires at the Elastic Waistband, who blocks it with his stretching belly.
SpongeBob accidentally puts the Dirty Bubble into a washing machine and he splits into duplicates. The Dirty Bubble later plans to end The Yellow Avenger's journey with the machine Jumbo Shrimp used in the third act. He also plans to hit SpongeBob with other small Dirty Bubbles.
Coincidentally, Tom Kenny previously starred in a skit on the 1990s show Mr. Show called "The Altered State of Druggachusetts," where he played a send-up of Reilly's character on the 1970s children's show Lidsville.
At one point, he went to Cancun with the Killer Shrimp, as stated in "Mermaid Man and Barnacle Boy V."
In "Mermaid Man and Barnacle Boy V," it is shown that the Dirty Bubble can make a human hand with fingers, as demonstrated when he points into a boat.