The episode continues from the point where Zabuza was attacked with his own technique and was washed far away and stopped as he hit a tree. Kakashi then throws some kunai at him to pin him down. As Kakashi tells Zabuza that his future is death and was about to kill him, Haku attacks Zabuza at the neck with needles. Appearing for a while and having a short conversation with Kakashi and Naruto then disappearing with Zabuza's body. Kakashi falls unconscious after that and we now know that using the Sharingan causes great strain to the body. Kakashi sense that Zabuza could be alive and the Hunter-Nin (Haku) was just an imposter. Kakashi then decided to train the team on how they could control their Chakra better and sets off to the forest. He shows the Genins how to place their Chakra at their feet and resumes walking up a tree vertically. At the first try, Sakura was the best and reach the top, Sasuke second and Naruto crappy as usual. The second half of the episode reveals finally Haku's real identity as he revives Zabuza from his pretend death.