Producers of the three programs scrapped plans to air on Monday night as the walkout kicked off, following a weekend of desperate talks to halt the strike.
The Tonight Show host Jay Leno briefly joined the picket line outside the NBC studios in Burbank, California--where his show is taped--after network bosses announced the show would immediately go into reruns.
David Letterman's The Late Show will also run a series of repeats this week, as will The Daily Show and a series of daytime talk shows.
The strike started on a noisy note as picketing writers began chanting loudly outside CBS and Paramount Studios in Hollywood early on Monday morning.
Those organized outside Paramount wore red strike T-shirts and carried signs reading, "Writers Guild of America on Strike."
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