Naruto Episode 100: The Sensei and the Student: Bond of the Shinobi
Episode 100 of 220 of Naruto, aired September 8, 2004, 25 minutes. Available with English subtitles and dub where released.
Episode summary
As Lee decides whether or not to go through with the operation, Gai decides to give him some motivation. Meanwhile, Tsunade frantically struggles to increase the operation's success rate.