Whilst pestering Squidward, SpongeBob and Patrick learn that their heroes, Mermaid Man and Barnacle Boy, are in fact living in the Shady Shoals underwater retirement home, and they then try to bring the two (Mermaid Man and Barnacle Boy) out of retirement, much to the annoyance of the geriatric Bikini Bottom superheroes who only want their TV to get fixed. SpongeBob and Patrick go through all kinds of hilarious antics, including painting the Boatmobile to faking a purse robbery, to reunite their superhero pals and eventually succeed, thereby creating Mermaid Man and Barnacle Boy's new show: The New Adventures of Mermaid Man and Barnacle Boy.
The phone gets broken, and when Mermaid Man hangs up the phone, a comic book bubble appears and dramatizes the words "HANG UP!". When Mermaid Man sits down, the bubble appears again and says "SIT!!".Will our heroes ever get their phone fixed? Tune in next week and find out. And when SpongeBob winks, the bubble appears again, saying "WINK!"
As of June 10, 2014, The Internet Movie Database (IMDB) gives this episode a rating of 8.2/10 based on 192 ratings by users. TV.com users give this episode a 8.6/10 based on 202 votes.
"Mermaid Man and Barnacle Boy" was ranked #37 during the Best Day Ever event on November 9–10, 2006.
2:00 PM: SpongeBob and Patrick walk into Shady Shoals.
This is the first appearance of Mermaid Man and Barnacle Boy.
The ironic thing about this is that in most comic books, the dramatization of simple words usually comes in on action fighting scenes, but in this SpongeBob episode, it exaggerates the word dramatization.
When SpongeBob and Patrick are first asking the man at the front desk to see Mermaid Man and Barnacle Boy, an article on the inside of his newspaper reads, "School Drop Out Rate Soars". This has double meaning because "school" is also the name of a group of fish.
The old captain is played by the man who guards the gates at Nicktoons Studios in Burbank, CA. He is also the inspiration for the character "Old Kid" from Invader Zim.
When Mermaid Man picks up the phone during the game of checkers, the phone's ringtone is number 11 of the thirteen bad words in "Sailor Mouth".
Running Gag: Mermaid Man screaming EVILLL! and SpongeBob and Barnacle Boy saying "There's evil afoot!"
This is the only episode in which the Mermalair is called the Sea Cave.
When Patrick takes the doughnut from the box, it is orange, but when they "unite", it is replaced with the chocolate one which was left in the box. After that scene, it changes to the normal doughnut again.
After Patrick takes SpongeBob's purse and peers out from behind the building, the purse is seen floating beside him.
Barnacle Boy puts the wrong ring on Mermaid Man's hand.
After Mermaid Man says the oath, both his and Barnacle Boy's rings disappear.
Mermaid Man illegally moves one of his checkers into a red space before the screen switches to "King Me!"
When Mermaid Man and Barnacle Boy say "Dogpaddle, away!" and start dog paddling, you can clearly see Mermaid Man's socks are missing. After, they return.
When Mermaid Man says "Up, up and away" while rocking, Barnacle Boy appears to be saying it too, but with no voice.