Quick recap
An adaptation of the Sasuke novel. He infiltrates an observatory that doubles as a prison to find a particle that can cure Naruto's illness, and Sakura slips in undercover to help. The two endure forced labor, decode star charts and find the particles in a crater. The director, Zansul, revives dragon beasts with forbidden techniques. After fights in which other prisoners sacrifice themselves, Sasuke defeats Zansul, and his cellmate, manipulated until then, redeems himself by protecting Sakura.
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