Penn Badgley (Greetings from Tim Buckley), Teresa Palmer (I Am Number Four), Alexis Bledel (Gilmore Girls) and Hill Harper (CSI: NY) have joined the already pretty good ensemble cast for writer/director Brian Horiuchi’s indie flick Parts Per Billion.

They join Frank Langella (Robot and Frank), Gena Rowlands (Yellow), Rosario Dawson (Sin City) and Josh Hartnett (Black Hawk Down) in the movie, which tells the story of three couples dealing with the same reality shaking event that threatens to tear them apart. The Magnolia-style ensemble movie is set just before a disastrous biological war.

The movie is currently shooting in Detroit, and will continue to do so through Christmas.