The first teaser spot for Guillermo del Toro's FX horror series The Strain is now online, but you've probably already seen it.  The spot premiered during the mid-season finale of AMC's The Walking Dead, but its content was intentionally vague in the hopes of sparking up a conversation.  Remember the "found footage" video of hordes of rats crowded the city sidewalks? Yep, that's for The Strain.

The Strain stars Corey Stoll, David Bradley, Mia Maestro, Sean Astin, and Kevin Durand. Carlton Cuse will step in as showrunner while del Toro remains onboard as an executive producer.  Hit the jump to watch the teaser.

Check out the teaser spot for The Strain below (via Bleeding Cool):

"He Is Here" viral video clip first aired during The Walking Dead's Season 4 MidSeason Finale on Dec.1, 2013 #TheStrain - Follow us on Twitter: @TheStrain_TV

Use Google+? Join +The Strain (Circle) and interact with other fans of the show! http://gplus.to/TheStrainTV

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