Eat or be Eaten: Panic in the Forest

is episode 28 of the original Naruto anime.

Synopsis
Naruto Uzumaki has to go to the bathroom and Sakura hits him and makes him go under a bush. When he comes out Sasuke starts hitting him and explains to Sakura that is not Naruto because Naruto had a scar on his cheek. Naruto transforms and reveals a Rain ninja and he and Sasuke start fighting. While they were fighting Sasuke spots Naruto and frees him after Sasuke beats the Rain ninja. After Sasuke tells Team 7 that they need a password, Sasuke tells them a password that is a bit too long and Naruto didn't remember it. After that Orochimaru appears, disguised as three grass ninja.

Sasuke and Sakura find Naruto and ask him the password. Naruto says it word for word, which is not like Naruto. After Sasuke tells him to show himself, Orochimaru appears. Meanwhile Naruto wakes up after being attacked and is attacked by a giant snake that swallows him. Back again with Team 7 Orochimaru swallows the scroll and then paralyzes them with fear. When Orochimaru tries to attack them and when he is about to hit them Sasuke attacks himself to beat the fear and escapes. Meanwhile Naruto is in the snake and has flashbacks after he realizes he has to get out of there he uses the Shadow Clone Technique to over feed the snake and make it explode. While Sasuke and Sakura were hiding and a snake attacks them after Sasuke throws some shuriken at the snake Orochimaru appears within the snake. When he charges at Sasuke more shuriken attack and Naruto enters the battle.