Final Facedown! Happosai vs. The Invisible Man

Taiketsu! Happōsai Buiesu Tōmeiningen (対決! 八宝斉VS透明人間) is the tenth episode in the third season of Ranma ½, Hard Battle, and is the 50th episode overall.

Happosai has been running amuck worse than usual, prompting Ranma and Akane to plot to take him down. Meanwhile, Soun and Genma return from training under a mysterious Chinese Ninjitsu Master, claiming to now have the skills to defeat their evil master.

Relation to the Previous Episode
None.

Just Another Day
Yet another school day has let out, but for the females of Furinkan High School, it's not a source of relief; Happosai is throwing yet another of his underwear raids. Though Ranma is at the forefront of the pack and trying to help, Happosai defeats him easily, something that Akane chastises him for. Aside from Kuno making an attempt to defeat Happosai in order to impress Akane, nobody sees any point to trying to catch up with the old pervert, and so they reluctantly head home.

In the streets of Nerima, Akane complains that Happosai is just getting worse with Soun and Genma out of town, while Ranma scornfully notes that they aren't much help even when they are present, as they simply run for cover when he so much as looks at them cross. Akane declares that they'll just have to take care of Happosai themselves, then, to which Ranma gleefully replies he's already working on a strategy to beat the old pervert. Any further conversation is cut off when they see a small crowd gathered around something on the street, which close investigation proves to be the battered, exhausted and desperately hungry fathers in question.

At home, the two grown men eagerly wolf down rice as Kasumi tells them she's had a talk with Happosai about bullying the weak, so please stop running away. Ranma idly adds that he really wishes they would stop being such grovelling cowards around Happosai, whereupon Soun Tendo declares that they haven't been just running away recently. Although he and Genma immediately spring into grovelling stances whenever Happosai pokes his head into the room, Soun explains that during a recent outing, while lost in the wilderness, they stumbled across the Chingensai Dojo, which they challenged in an effort to get some food money. After they came to from their defeat, the titular Master Chingensai revealed himself to be the heir to a 3000-year-old tradition of Chinese Assassins; naturally, the two of them begged to become his disciples and learn his secrets, hoping to turn them against Happosai.

The training was long and rigorous, involving purifying meditation-baths under icy waterfalls, sumo-wrestling the local bears and dragging massive weights back and forth. Ranma and Akane are skeptical of Soun's claims, especially when they eagerly accept Happosai's offer for a little party and proceed to make fools of themselves for the perverted grandmaster's amusements, explaining their actions away as following Chingensai's "Super Secret Ninja Tricks" numbers 1 ("All things come to he who waits"), 2 ("To fool your enemy, it is first neccessary to fool your friends) and 3 ("Blessed is he who expects nothing, for he shall never be disappointed").

The Next Day
When the next day rolls around, and with it the time for Happosai to make his panty raid, Soun and Genma see him off with humbleness and grovelling, then, once he is out of sight, quote Chingensai's "Super Secret Ninja Trick #4": don't fix it if it ain't broke.

While awaiting Happosai's assault, Akane and Ranma express their disdain for the previous night's charade, with Akane declaring it a new low, even for them. Ranma declares that they'll just have to handle this themselves, asking if Akane remembers her part in the plan. When Happosai comes storming out of the girl's locker room, Ranma distracts him with a paper bra, then kicks him from the air and throws his bag of loot to Akane, waiting in the bushes.

Akane quickly removes all of the women's underwear and replaces the bag's contents with something else, but she and Ranma have failed to count on Happosai's unpredictability; before she can finish, a crying Happosai knocks Ranma through the bushes and leaps over in pursuit, stopping his threat when he sees Akane with his bulging sack in her lap. Surprised, and actually sounding rather pleased, he notes that he never knew Akane shared his enthusiasm for underwear. Akane, needless to say, isn't pleased at being compared to the old pervert, and promptly sends him and his tampered sack skywards, telling Ranma that she managed to load it up as planned.

Having the nerve to hide out on the schoolground, Happosai starts to go through his latest haul - only to get the shock of his life when what he thought at first glance to be girl's underwear turns out to be a boy's jockstrap. Ranma, Akane and a gang of students of both sexes corner Happosai, as Ranma reveals that Happosai has been tricked - all of the girl's underwear has been taken and given back, and all he currently has is an array of ruby team jockstraps, wrestling team leotards and sumo club loinclothes, not one of which has been washed once in the last week.

Disgusted, his energy sapping away quickly, Happosai tries to flee, with Ranma and Akane in hot pursuit. While Happosai does manage to dodge Ranma's intial attempt to hit him, Ranma's "Terrifying Man Musk Project" has really sapped his strength and the rebounding ball knocks him flat onto his face. When he doesn't move for several minutes, Akane begins to step close, worried, but Ranma quickly shoots forward and stomps Happosai into the ground before he can do more than desperately scrabble in an effort to launch himself at Akane's breasts. The two teens demand that Happosai stop stealing, to which Happosai protests that if he can't steal undies, peek up skirts or grab girlies, they may as well kill him and get it over with.

Soun and Genma Return
Suddenly, the sound of maniacal laughter rings out as Soun and Genma appear. Soun tries to make an excuse about why they haven't shown up to help the kids take down Happosai before now, but trails off when it becomes clear that there isn't none. With the battle cry of "Super Secret Ninja Trick #5 (If it is broke, make sure it says that way)!", they leap upon Happosai... who promptly pulls out a bra he had concealed on his person, bringing them to a sharp halt. Akane manages to grab it back before Happosai can get too much energy back, but he still has enough pep to easily handle Soun and Genma's Twirling Plates of Destruction attack and then counter with some Happo Fire Bursts. Genma manages to reflect the force of an explosion by catching the bomb in a wok, whereupon he and Soun start throwing Pot Sticker Bombs at the old pervert, eventually leaving him a battered heap on the ground.

Once this is done, the two men decide to show off their newly learned ultimate attack; "Now You See Me, Now You Don't", vanishing before the startled eyes of all three. But in the confusion, Happosai latches onto Akane, managing to regain a great deal of his strength, then unceremoniously revealing that the "disappearing act" was simply Soun hiding under the ground while Genma slipped behind a painted screen to blend into the trees. They promptly start cowering in submission to Happosai, who expresses disgust at their antics, whereupon Ranma attacks Happosai himself. With the aid of the wok that Akane throws to him, he shields himself from Happosai's barrage of bombs and then traps the old pervert in one of his own explosions... but when he lifts the wok, it looks like Happosai has disappeared.

Genma immediately starts begging for his life, much to even Soun's disdain, but Akane spots the wok sneaking off - Happosai used one of the oldest tricks and hid inside the wok when it was lifted off, going unnoticed because they expected him to be on the ground. Caught, exhausted and beaten, Happosai makes that he is going to leave graciously... only to shout out Soun and Genma's previous attack name and vanish himself. As he chastises the men, swiftly reduced to grovelling, he also has invisibility tricks in his arsenal - they have now seen the Extra Dimensional Warp - and is insulted that they didn't think he would.

To everyone's surprise, an unfamiliar voice rings out - but Soun and Genma recognize it as Chingensai, who they beg to save them. To their growing horror, he reveals he is most certainly not going to help them and couldn't care less about them. Indeed, he thinks they are idiots for falling for the "cheap bit of razzle-dazzle" that the Now You See Me Now You Don't represents; while nobody can attack a person using it, the user can't attack without instantly forfeiting the protection of the invisibility. For an added stinger, he materialises and reveals he developed it so that he could sneak in and out of women's locker rooms - whereupon Happosai also materialises, declaring his Extra Dimensional Warp has an identical nature and purpose.

Tears in their eyes, the two old men greet each other - it turns out that the master Soun and Genma ran away to study under is the best friend of the master they ran away from, something that Ranma calls a weird sort of fate. Revealing that his dojo overlooks a women's college dorm and inviting his old friend to come and stay, the two elderly perverts snap at Soun and Genma to give them a lift, and Ranma & Akane can only watch as the terrified masters of the Saotome and Tendo Schools grab a grandmaster each and set off running for the Chingensai Dojo.

Trivia

 * Chingensai may be an inspiration for the much later manga-exclusive character Rakkyosai, though Chingensai has a much better relationship with Happosai than Rakkyosai does.
 * In the subtitled version, Chingensai's style is said to be "Mandarin Ninjitsu", implying he met Happosai during his youthful "adventures" in China.
 * In the dubbed version, Kuno makes a reference to Lancelot and Guinevere from the Arthurian myths of the west.
 * In the subtitles, Kuno gives himself a new nickname; Immortal Phoenix.
 * This is the first episode since he learned it that Happosai has used his Happo Fire Burst technique.
 * In the subtitled version, Chingensai's "Now You See Me, Now You Don't" is called "Body-B-Gone".