Naruto Episode 18: The Weapons Known as Shinobi
Episode 18 of 220 of Naruto, aired February 6, 2003, 25 minutes. Available with English subtitles and dub where released.
Episode summary
Kakashi prepares to stop Zabuza once and for all, but Haku has other plans. Zabuza's employer shows up and he's decided to take matters into his own hands...