360 Degrees of Vision: The Byakugan's Blind Spot

is episode 116 episode of the original Naruto anime.

Synopsis
Kidomaru manages to shield himself form the attack, and flees to the safety of the neighboring trees. Deciding to attack Neji from a distance, Kidomaru advances his cursed seal to its first level and sends multiple spiders to attack Neji. Neji is able to repel them all, though Kidomaru notices a delayed reaction in some of Neji's blocks. He theorizes that Neji's defenses have a blind spot, and attacks him further from this blind spot. His theory is proven correct as Neji is unable to block the attack. Believing himself to have found Neji's weakness, Kidomaru prepares to finish the battle.