AMC series "Mad Men" and "The Killing" will each have two-hour season premieres a week apart, on March 25 and April 1 respectively.

The long-awaited fifth season of "Mad Men," which hasn't aired a new episode since 2010, will launch at 9 p.m. before settling into its 10 p.m. slot the following week after the second season of "The Killing" unfolds. "Killing" will normally air at 9 p.m.

"The Walking Dead" had its third season extended to 16 episodes, up from 13. "The Walking Dead" is returning with a new episode Feb. 12, followed by the premiere of unscripted series "Comic Book Men" exec produced by Kevin Smith.

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