Nagi decides to take Hayate and Maria on a trip to visit a mysterious meteorite that seems to enhance growth, along with other special powers. On the way there, Nagi accidentally leaves the train to buy a box lunch, but then the train leaves without her and she becomes lost all alone. Nagi meets up with Ayumu after eating at a ramen shop and Ayumu lets her ride on the back of her bike to take her to the next train stop. Meanwhile, Hinagiku tries to talk to Maria for advice about love, but they are interrupted by a call from Nagi. While waiting on hold, Nagi and Ayumu meet some hit men who say they need to take out Nagi but do not know which one is her due to both of them having pigtails. Ayumu pedals away on her bike, and Hayate is on the same road, looking for them.
伊豆半島に謎の隕石が落下。下田付近の温泉では、隕石の影響か、特殊な効能が現われている模様。その効能とは、『胸が大きくなる』、『理数系の成績がアップする!!』、『神秘の力が使えなくなった人は力が回復する』。こうして、それぞれがそれぞれの目的のもと、静岡県下田温泉を目指すことになるのだが…。
