Woody Harrelson, Pete Davidson, Tiffany Haddish and John Goodman are set to join the voice cast of the adult animated series The Freak Brothers, which is currently being shopped to networks. The Freak Brothers is based on Gilbert Shelton's underground comic The Fabulous Furry Freak Brothers, which was first published in May 1968 in an underground newspaper called The Rag that operated out of Austin, Texas. The comic was about a trio of stoners and their adventures procuring their precious plant, at once critiquing the establishment and satirizing counterculture. The eight-episode series was announced last year at Comic-…