"Can You Open the Ten-Year Vault?"note , with the English title "A Safe Bet". Released in 2003 by Geneon on Volume 4: Thieves' Paradise.
At a lavish business party for a group of clients, a hostess shows off an elaborate ring, which is actually a custom safe by renowned safe maker Marukin made to keep the ring's valuable jewel safe inside. The party winds down, and the host and hostess are annoyed to find one guest, a rather large woman, still drunk and partying. They decide she's fine to stay and head off to more private areas of the house; after they leave the room the woman sobers up and gets a gleam in her eye. As the hostess prepares for bed, the large woman suddenly smashes through the window with a mischievous grin. Shortly thereafter, Marukin himself is summoned to the house, where the ranting host notes that every single safe Marukin hid in the house has been opened and emptied, including the one on his wife's finger. As the lady swoons, a cocky Lupin rips off his elaborate disguise and flies off into the distance.
Jigen later reads in the paper that Marukin and his safe company are suffering because of Lupin continuing to defeat the safes' elaborate mechanisms. Lupin declares he is merely forcing the company to innovate. As Jigen continues to read the article, Fujiko, upon hearing that Lupin "comforted" his target's wife, storms out.
Meanwhile, Marukin, surrounded by his returned and unsold stock, vows revenge on Lupin. He remembers his "ten-year safe" at the Mitsuboshi Bank, which only can open once every ten years, no matter what is done to the door. He decides to challenge Lupin to open it before the deadline, in hopes Lupin will humiliate himself and restore Marukin's good name. Lupin sees the challenge, and in spite of Jigen and Goemon's advice, decides to blindly accept to show that his earlier attempts were not just dumb luck.
Zenigata finds out about the challenge and meets with the bank manager, who is not thrilled with Marukin's stunt. When Marukin joins the meeting, the bank manager has stated that Marukin's contract is canceled, but Marukin is so sure of success that he laughs the manager's news off. Therefore, he is distraught when the manager tells him that the bank safe has already been opened and emptied, even showing it to Marukin, in its hidden spot behind the wall. Marukin leaves in a mad fury. After Zenigata heads out, the manager pulls off a mask, revealing himself to be Lupin and the "opened" safe an elaborate painting over the real safe door. All he and Jigen need do is wait for the safe to open on its own to empty it.
Elsewhere, Fujiko takes a stroll through a peaceful temple and forest, followed by a young, bald man in a kimono. When confronted, the man greets Fujiko and shows a photo of her and the rest of the gang hanging out. He introduces himself as Jotaro, Marukin's son, and asks Fujiko to introduce him to Lupin, seemingly glad that the thief outwitted his father. Since he's just a boy, Fujiko indulges Jotaro and takes him to the gang's hideout to meet Lupin. In the sauna, Lupin has a chat with Jotaro, confessing there was no real reason for targeting Marukin's safes over any others. Upon hearing this, Jotaro holds the sauna shut and turns up the heat on Lupin, literally. After an overheating Lupin confesses that he targeted Marukin simply to demonstrate his own skills, Jotaro tells Lupin about the shame the thief's pride caused his family. He even accuses Lupin of "cheating" on the last safe, since he didn't actually open it via his safecracking skills. As he rants, he brings Lupin closer and closer to scalding levels of heat in the sauna. Jotaro then challenges Lupin to open one last safe, a special one of his own creation. Lupin refuses, and so Jotaro leaves him to roast.
Back in the living room, the rest of Lupin's gang tries to talk Jotaro out of his attempt at revenge. The boy pulls out another special design: a safe-like set of handcuffs. When Fujiko attempts to retrieve some darts on the wall, he slaps them on her wrists. Jotaro then informs the gang that the key to the cuffs is in the special safe. Goemon threatens Jotaro, but Lupin, exhausted and overheated, arrives just in time to stop him. After retrieving a drink from the fridge, he attempts to pick the lock on the handcuff safes. While the gang is focused on watching Lupin, Jotaro drops some powder in the thief's drink. After the dehydrated Lupin empties the glass, Jotaro informs him that the drink was poisoned, and the only antidote is in the same safe as the handcuff key!
Jotaro takes the gang to his specially designed safe, lying out in the middle of a field. It is egg-shaped and completely smooth, with no visible doors or cracks; the boy informs Lupin that opening the safe is as simple as the safe's design. Jigen first fires bullets at the egg, which ricochet off. Goemon's attempt to open it via sword is likewise thwarted when the blade breaks. Lupin then uses all of the tricks and tools at his disposal, from stethoscopes to drills, but the safe isn't even scratched. Lupin is fading fast, but he refuses to give up. Desperate, Lupin wonders aloud if the safe isn't just some kind of trick, and when Jotaro gloats over Lupin's imminent death, Lupin weakly but sarcastically wonders if it isn't some dumb gag like "Open sesame."
The safe splits open. Goemon quickly administers the antidote to Lupin while Jigen unlocks Fujiko's cuffs. Jotaro finally admits defeat, and decides to continue to improve himself until he is worthy to challenge Lupin again. Fujiko kindly tells him he has already made himself worthy of his father's name. After the boy leaves, Lupin decides to use "open sesame" again, this time on Fujiko's legs. Fujiko administers swift slapping justice, but Lupin admits it was worth a try.
This episode features examples of:
- Absurdly Sharp Blade: Averted. Zantetsuken breaks, and Goemon seems remarkably unconcerned!
- Creepy Crossdresser: The woman Lupin dresses up as was not...attractive. Lampshaded by Jigen, who hopes that Lupin didn't seduce his first target's wife while still in disguise.
- Disguised in Drag: Lupin's elaborate guise at the beginning of the episode.
- Gonk: Lupin's fat lady disguise.
- Graceful Loser: While outwardly disappointed at the outcome of his challenge, Jotaro gracefully admits his defeat at the hands of Lupin (though with a promise to confront him again in the future after he has sufficiently honed his skills), rather unlike his father.
- Hypocritical Humor: Fujiko's comment that Lupin is a "bad person" for ruining Marukin's company. How many has she infiltrated and ruined?
- Implausible Fencing Powers: Averted. It never seems to occur to anyone for Goemon to try and use his sword skills to take off Fujiko's handcuffs.
- Ironic Echo: Goemon tells Lupin to "open sesame" so he can administer the antidote, and Lupin says it again when he kneels down in front of Fujiko.
- Life or Limb Decision: Goemon offers to help Fujiko get the handcuff safes off... by removing her hands. She is not amused.
- Open Sesame: The magic words to open Jotaro's safe.
- Pac Man Fever: Lupin and Fujiko are playing a game of Pong in one scene. Justified, as the series was made in a time when videogaming was still in its infancy, and the Atari 2800 didn't reach Japan until 1983. See also Unintentional Period Piece below.
- Prematurely Bald: Averted; Jotaro explains he thought it would "look cool." Fujiko agrees.
- Sarcasm Mode: It saves Lupin's life in the end!
- Sauna of Death: How Jotaro tortures Lupin.
- This Is No Time to Panic: Goemon, just before he breaks his sword. Followed by the classic Verbal Backspace, "Alright, now you can panic."
- Torture for Fun and Information: Jotaro uses one on Lupin, via a sauna and an adjustable thermostat that apparently goes into "broil".
- Unintentional Period Piece: One scene has Lupin and Fujiko play a game of Pong. This is lampshaded in the dub when Lupin jokingly suggests that Jotaro challenge him in a game of Frogger.
- What the Hell, Hero?: Jigen and Goemon's reaction when Lupin wants to prove himself, even though he will completely send Marukin into ruin.