Cartoon Network animated series running from 2001-2005 (with season 5 in 2017) depicting a samurai who is sent to the future by the demon Aku, and must return to his own time to stop him("Gotta get back")
Samurai Jack was a series conceived by Gennedy Tartakovsy (powerpuff-girls, dexters-lab), which featured a samurai sent to the future by the demon Aku. Jack is not actually his name (being from the feudal Japan era), but the citizens of the future begin to call him Samurai Jack.
The series drew lots of praise and acclaim, despite being a cartoon series for kids, for its unique artwork and artistic stories. The series ran from 2001-2005, airing during daytime slots and featuring Jack fighting mostly robots (who could be hacked and slashed at will).
Season 5, aired during the late night Adult Swim, turned the series darker. Time skipping 50 years, Jack is a man tormented by his inner demons. We also see him fight flesh-and-blood foes (complete with blood). The fifth season completed the story.