Kakashi Love Song
A female spy, Hanare, from the Hidden Lock Village (Land of Key) is caught by ANBU pretending to be a musician. She is interrogated. However, the interrogation proves unsuccessful. Slowly, her past is revealed and so is her relationship with Kakashi. Team 7 spy on the two as they go around town, under the impression that the two are dating. After The Lock Village keeps a Leaf Village ninja hostage, they exchange Hanare for the ninja. It is then revealed that Hanare has a special ability, causing a large chase to occur. In the end, Kakashi lets Hanare free. The musician seen at the beginning entertaining Konoha ninja reminds Kakashi of Hanare which prompts the flashback.
Aired 16/12/2010EP 191 - Kakashi Love Song
Naruto: Shippuden
Naruto: Shippuuden is the continuation of the original animated TV series Naruto. The story revolves around an older and slightly more matured Uzumaki Naruto and his quest to save his friend Uchiha Sasuke from the grips of the snake-like Shinobi, Orochimaru. After 2 and a half years Naruto finally returns to his village of Konoha, and sets about putting his ambitions to work, though it will not be easy, as he has amassed a few (more dangerous) enemies, in the likes of the shinobi organization; Akatsuki.
(Source: Anime News Network)