Episode XXXVI: Jack, the Monks, and the Ancient Master's Son

Episode XXI: Jack the Monks and the Ancient Master's Son is the thirty-sixth episode Samurai Jack. This episode features Jack discovering a temple of monks that belonged to the same order that Jack had once trained with before his showdown with Aku. He also discovers that the Ancient Master knew Jack in the past. When Jack was still a teenager, he was finished with a day's worth of training and a little boy gave him some water. That little boy was the Ancient Master.