While there, Jake also hoped to find Rose, knowing she and her family moved there, after her wish for the destruction of The Huntsclan altered reality, so she had never been taken from her family as a baby, thus forgetting Jake as a consequence. Jake's friends then told him to forget about Rose and move on and find someone else, but Jake then quickly changes the subject and decides to take a look at the view, but Gramps tells Jake why they really went to Hong Kong: During the eclipse tomorrow, Grandpa, Jake, and Haley all must attend the One Thousand Year Toast at Victoria Peak, where the first Dragon Temple was built, which only appears once every thousand years. Fortunately, it only lasts a couple of hours, so for the rest of the time, they are free to enjoy their vacation.
Meanwhile, the Dark Dragon plots to destroy Jake and The Dragon Council as a final step before taking over both the magical and mortal worlds. He sent Chang to kidnap Grandpa, which led Jake, Trixie, and Spud into a trap where the Dark Dragon and Jake fought, with the Dark Dragon dominating. When Grandpa appeared, Jake tried to rescue him, but he was pinned down. With that, the Dark Dragon gives Jake an ultimatum: He is to spike the Dragon Toast with a mind-controlling potion, or else he'll never see his grandfather again. Jake, realizing the great power that the Dark Dragon had gained, decided he needed help in dealing with him. Sending Trixie and Spud, with Jonathan as a tag-along, to search for the local Huntsclan installation – its existence, despite the wish, is unknown – Jake sets out to find Rose in hopes that, even if she no longer remembered being a Huntsclan member, she still had a natural ability to fight dragons.
He confronted Rose outside of her school, trying to get her to remember and help him at Victoria Peak. Unfortunately, Rose was initially convinced he was an insane stalker and under the pretense of allowing him into her home in order to prove he was a dragon, had actually called her parents, who in turn had called the police. However. something about Jake resonated with Rose and she felt bad about him being taken away. She then found in the jacket Jake had left behind a photo of them which had survived the wish by having been on his person at the time.
Jake shifted into dragon form to escape from the back of the paddy wagon and flew for to Victoria Peak. Meanwhile back at the hotel, Fu Dog informed Jake's mother about the trouble Jake was in, and when Haley transformed into her dragon form, ready to help, her father Jonathan accidentally walked into the room in time to see and fainted. After gaining consciousness, finally learning the truth of his family and the trouble Jake and Grandpa were in, Jonathan decided to join them and take all of them to Victoria Peak to help defeat the Dark Dragon.
At the One Thousand Year Toast, Jake offered to serve the drink from the Golden Cup, spiking it as ordered, knowing the Dark Dragon was watching from afar. Once all had drunk, the Dark Dragon flew in and commanded Sun Park to kill one of the Dragon Council members there. However, she appeared to struggle against carrying out the order, before she, and the rest of the dragons, all changed into different animals, which was when Jake revealed he had switched the potion with Transformation Tea in order to lure the Dark Dragon out, bringing Grandpa along to be killed with them all.
Which was when Jake's friends and family showed up and together with the Good Dragons, returned to their original forms when the Transformation Tea wore off, engaged in final battle with the Dark Dragon and his shadowy minions. Despite having just learned of the magical world, Jonathan held his own, with he and Susan using his flash camera and a bejeweled chalice to banish many of the Shadow Demons.
Rose also appeared in time to help Jake at the battle's climax, the photograph having helped restored her memory. As the eclipse event which anchored the temple in reality drew to an end, and the temple was about to disappear for another thousand years, all the dragons and mortals fled outside. Unfortunately, Rose remained fighting off the Dark Dragon and they were both trapped by falling debris. Jake flew in to rescue her, determined to not lose her again. The Dark Dragon however, grabbed a hold of Jake's leg with his tail, determined to trap them all, however Rose used her Huntsclan staff weapon to cut them free.
Just as the vortex closed, Jake and Rose barely escaped to the applause from all the dragons and Jake's family and friends. Rose passionately kissed Jake, showing him the photo and how her memory had been restored by it.
As they all returned to their hotel room, Jake mentioned that, although his father had only just found out he had married into a family of dragons, that he was taking the news pretty well. Jonathan responded that he guess he had always known there was something "magical" about his family. Jake replied, "Trust me, there's something magical about you too", and hugged his father.
Jonathan Long finally learns the secret about his family.