SpongeBob and Patrick are strolling through Bikini Bottom and see Mermaid Man and Barnacle Boy in the Invisible Boat Mobile, without gas. SpongeBob and Patrick push the boat over several hills. Barnacle Boy invites them into their warehouse full of memorabilia from their T.V. show. Barnacle Boy shows them a time machine which they have never used, and warn them to not use it. But Patrick mistakes it for a vending machine, and all of them are transported to 1954 when Mermaid Man and Barnacle Boy are young. They see Man Ray tormenting old Bikini Bottom. Mermaid Man and Barnacle Boy are unsuccessful at foiling Man Ray due to Patrick eating the tartar sauce they were originally going to trap him in. SpongeBob and Patrick escape old Bikini Bottom, leaving their Mermaid Man and Barnacle Boy behind. When SpongeBob and Patrick return to Bikini Bottom, it is no longer called Bikini Bottom, but Man Rayopolis. They go to the Krusty Krab which now has no name. The superheroes from their time are now dead and buried inside of the restaurant. While the past superheroes now work there. Mermaid Man is the fry cook, SpongeBob's position, and Barnacle Boy is the cashier, Squidward's position. They go back to stop Patrick from eating the tartar sauce, but the heroes who were sent by accident believe they are impostors. The Mermaid Men fight which creates the perfect distraction for Man Ray. The young Mermaid Man and Barnacle Boy attempt to foil Man Ray with the tartar sauce, but the two Patricks end up eating it. Another warehouse appears. SpongeBob and Patrick from a different time period emerge from the warehouse screaming "Patrick, don't eat the tartar sauce!" Another warehouse appears above of Man Ray and out fall SpongeBob and Patrick. Yet another one appears with SpongeBob saying to Patrick "I told you we had to go back further!" Another one pops to Man Ray's left with Mermaid Man and Barnacle Boy leaping out of it exclaiming " Up, up and away!" They both fall headfirst into the ground. Another one appears above of the previous warehouse with the superheroes. SpongeBob and Patrick appear and throw a batch of tartar sauce over the fallen superheroes from the previous warehouse. Another one appears next to the pair of warehouses. Man Ray flies out of it, destroys it, says, "I took care of your blasted time machine!" and leaves. All of the warehouses appearing in random locations confuses Man Ray. Man Ray sits down on a log and thinks about what is happening, but gets arrested by the superheroes. Then all of a sudden many warehouses appear all over the planet, all of them containing multiple copies of SpongeBob and Patrick.
Home video releases
- SpongeBob SquarePants: Heroes of Bikini Bottom
- SpongeBob SquarePants: The Complete 7th Season
- In this episode, Barnacle Boy refers to the Invisible Boat Mobile as "The Invisiboat".
- "Back to the Past" aired in the UK on April 2, 2010.
- The original past when Man Ray is brought to justice via tarter sauce can be referenced to Mermaid Man and Barnacle Boy III where Man Ray is shown to be entombed in frozen tarter sauce.
- This episode could possibly explain why Man Ray has turned good in "Mermaid Man and Barnacle Boy III", but is still evil in most other episodes after it. As they altered the future, so Man Ray was never frozen in Tartar sauce to later be awakened, and turn good. Instead he went straight to jail, thus he remained evil.
- Running Gag: Whenever there was tartar sauce, Patrick would eat it up.
- When tons of objects fall down on Mermaid Man, Man Ray's head is visible and can be seen falling down on Mermaid Man's head.
- SpongeBob says "jaywalking" in this episode. The term "jaywalking" and Ernest Borgnine's birth had happened in the same year.
- This is the first episode in which Squilliam appears without Squidward.
- The title of this episode is a reference to the film: Back to the Future.
- Man-Rayopolis is a play on George Orwell's "1984". The poster featuring Man Ray's eyes watching SpongeBob and Patrick with the words, "He's watching you" is a reference to 1984's famous phrase, "Big Brother is watching you".
- Young Mermaid Man and Barnacle Boy were played by Adam West and Burt Ward, who played Batman and Robin in the 1966-68 live-action Batman TV series.
- Another refrence to Back to the Future is that Spongebob and Patrick time-traveled to 1954, while Marty Mcfly traveled to 1955.
- When SpongeBob and Patrick are traveling back to the present, the clocks are moving backwards instead of forwards.