Inspirational 20+ Thora Birch Hocus Pocus Walking Dead. The walking dead on sunday introduced hocus pocus star and season 10 newcomer thora birch, who plays newly revealed whisperer gamma. How did this whole casting process go down where you ended up playing gamma? The etruscan smile opens this friday, november 1st at the laemmle pasadena and laemmle encino. I tried to walk a fine line between being alluring and somewhat glamorous but maintain a strong identity and pursue things that were a little more.