'Mad Men' and 'Freaks and Geeks' Collide, Creating an Internet Frenzy

The appearance of Linda Cardellini -- aka Lindsay Weir -- on the AMC drama set off a wide range of shocked reactions online.
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The comfortable alternate universe of television mythology exploded on Sunday night, as two worlds collided in the fuzzy fictional anti-matter and ripped a hole in the space-time continuum of continuity.

Could it be: a grownup Lindsay Weir, sleeping with Don Draper, eleven years before she ever ran away from home to follow the Grateful Dead that one liberated summer?

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Yep. Linda Cardellini, with a bob wig and slightly creased smile, had everyone's favorite existentially troubled ad man between the sheets. Chalk it up as the biggest surprise at the end of the two-hour season six premiere of Mad Men on Sunday night, creating as much chatter as any other element of the brooding and death-obsessed episode.

Cardellini has established a long and distinguished acting career in the decade and a half since she starred as the lead in the short-lived Freaks and Geeks, but she will forever live on as the rebellious teenager of Paul Feig and Judd Apatow's creation. And thanks to our tendency to hold on to the past for dear life, the community watching and snarking on Mad Men on Sunday reacted with a collective gasp and OMG.