Comingsoon: Sean Astin ("The Lord of the Rings") has joined the cast of Nickelodeon's all-new CG-animated "Teenage Mutant Ninja Turtles" as Raphael, one of four teenage brothers dedicated to a life battling evil denizens. Rounding out the cast are Jason Biggs ("American Pie") as Leonardo, Greg Cipes ("Teen Titans") as Michelangelo and Rob Paulsen ("Planet Sheen") as Donatello. Paulsen also voiced the original Raphael from 1987-1996 in the first series. Currently in production at the Nick Animation Studio in Burbank, Calif., the show is set to premiere in fall 2012. Executive produced by Ciro Nieli, Joshua Sternin and J.R. Ventimilia, this half-hour action-comedy series breathes new life into the wildly popular band of reptile brothers.