Avengers: Season 1, Episode 16: "The Man Who Stole Tomorrow"

"The Man Who Stole Tomorrow" - Kang the Conqueror has arrived in the 21st century with two goals…destroy Captain America and take over the world. The Avengers aren’t about to let either happen...until Kang explains why. Because in the near future, the Earth will be destroyed. Kang has come to save the world, and the Avengers are standing in his way.