The Marvel Action Hour, later Marvel Action Universe, was a 1994–1996 syndicated television block from Genesis Entertainment featuring animated adaptations of Marvel Comics superheroes Fantastic Four and Iron Man, with Biker Mice from Mars added for the block's second season.^[1] It aired in syndication^[2] for two years before being cancelled.^[3]

The first half of the hour was an episode of Iron Man;^{[4][5][6][7][8][9][10][11]} the second half, an episode of Fantastic Four.^{[12][13][14][15][16][17]} During the first season, Stan Lee introduced the episode.^[12]

Both the Fantastic Four^[18][19][20] and Iron Man^[21] were radically retooled^[22] for the second seasons, sporting new opening sequences, improved animation,^[23] and more mature writing, though the introductions by Stan Lee were shortened and now against a green screen displaying various production paintings from both shows.^[24]

In most markets, the second season was known as Marvel Action Universe, which was the name of a previous syndicated programming block in the late 1980s, with the addition of Biker Mice from Mars extending the block to 90 minutes.^[1] The structure was like this: there was a pre-opening overview^{[25][26][27][28]} of the each respective series, then the Marvel Action Universe opening,^[29] then the Stan Lee intro, then the episode prologue, then the regular show opening, and finally the episode.

• Iron Man and Fantastic Four (September 24, 1994 – February 24, 1996)
• Biker Mice from Mars from the second season.

Generally, New World owned television stations broadcast The Marvel Action Hour along with generally Fox, The WB, UPN, or independent stations in markets where New World did not own a station.

• Spider-Man (1994 TV series)
• The Incredible Hulk (1996 TV series)
• X-Men (TV series)