An advertisement for free interest from the bank broadcasts on the Krusty Krab's TV. Mr. Krabs hears about it and leaves SpongeBob SquarePants in charge of the Krusty Krab as he rushes to the bank. Mr. Krabs notices that people get interest. Mr. Krabs over-obsesses about money, and Nancy presses a button for guards to kick him out. Mr. Krabs disguises as a mustachoid man, but the disguise fails.
Mr. Krabs disguises again, but as a woman, and Nancy told him he had to make a deposit. Mr. Krabs chooses to deposit only a penny but is anguished. While saying goodbye to his penny, he falls down to a room full of money. He arranges this pile of money into a restaurant. SpongeBob sees that Mr. Krabs is gone. He goes to Pearl, then he calls Mr. Krabs, who says he is running out of oxygen. He then goes to Patrick and asks for his help to break in a bank. Patrick does a spit-take and is shocked at how crazy this is, only to say it is great. SpongeBob and Patrick arrive at the bank and discuss how to get it. Patrick brings some shoelaces, and SpongeBob grapples them to the roof. The shoelaces untie themselves, and he falls. Patrick brings a grappling hook, but it also fails after they took the vent that led that back at the front. He has a key, and SpongeBob commands him to use finesse. Patrick uses his "finesse", but the bank opens at the same time, causing Patrick to run off. Mr. Krabs hallucinates and imagines himself on a beach with a woman made of money, only for the beach to be on fire. The money is the sucked by a vacuum cleaner, which is a dragon in Mr. Krabs' imagination. SpongeBob breaks in but takes his ski mask off. He requests a bank guard to withdraw one Mr. Krabs. The guard sees Mr. Krabs breaking the vacuum cleaner, and promptly kicks him out with SpongeBob, along with his "deposit." Mr. Krabs is angry that the bank didn't even give him his free interest, but gets another penny thrown at him, then says he doubled his money.
This is the second time SpongeBob and Patrick attempt to break into a place. The first was in "Doing Time."
This is the second time Eugene H. Krabs dresses as a woman to get to money. The first was in "The Cent of Money." In fact, the outfit he wears is similar if not the identical to the one he wore in that episode.
The Bank Manager has a similar personality and voice to the Bikini Bottom Mint tour guide, Bill. They both seem to have calm voices even when angered. Ironically, both of them work in similar lines of occupation.
It is unknown how the vacuum cleaner ended up in the safe with Mr. Krabs.
Although Nat Peterson is seen as one of the officers that escorts Mr. Krabs out of the bank, he is later seen at night in the Krusty Krab, out of uniform, eating a Krabby Patty. This may be because the Bank of Bikini Bottom Bank closed up for the night (as Nat accidentally locked Mr. Krabs in the safe before leaving).
Funny that in this episode, Officer John and Nat Peterson play somewhat major roles. Officer John and Nat currently hold the record for having a major role in a single episode being a Bikini Bottomite (Nat Peterson's role in "Plankton's Regular," and Officer John's role in "Keep Bikini Bottom Beautiful").
Usually, in order to open a safe deposit box, one must have two keys: their own and the bank's. Nancy Suzy Fish only used one key and was never shown giving Mr. Krabs a key.
Mr. Krabs should have stored all of his money in the bank, then he would have got double his money, and he could then take out the money right after he got the interest.
When SpongeBob asked Patrick about having shoe laces, he said that it was the closest to him of having shoes. However, he wore shoes in "Your Shoe's Untied," which may believe that this episode took place a little before that episode or he just forgot.
In the Hebrew version of this episode, there are no words in the title card.
Mr. Krabs was running out of oxygen while in the safe despite the fact that it was underwater and nobody breathes oxygen.
This episode's title is a pun of "safe deposit box."
The "double the money" promotion in this episode is similar to what Credit card companies do to advertise their credit cards and get customers that use their credit card.
When Mr. Krabs ran out of the Krusty Krab to get to the Bank of Bikini Bottom Bank, in that shot, the road that leads to the Chum Bucket is not there. The Chum Bucket itself isn't even there.
When SpongeBob and Patrick are at the door, and Patrick is attempting to pick open the locks of the bank doors, the horizon is still night dark. Yet when the bank manager changes the "Closed" sign to "Open" and opens the doors, it immediately turns to morning.
It is unknown as to how the bank manager knew SpongeBob's last name. SpongeBob never told him.