Sean Astin is an American actor who portrays Bob Newby in the second season of Stranger Things. Before Stranger Things, he was known for his film roles as Samwise Gamgee in Lord of the Rings series, Mikey Walsh in The Goonies, the title character in Rudy. In television, his roles include voicing Raphael in the 2012 Nickelodeon Teenage Mutant Ninja Turtles TV series, Oso in the Disney Junior show Special Agent Oso, and Chester The Cat in Bunnicula.
On November 7, 2016, it was revealed that Sean Astin had been cast for Season 2 of Stranger Things in the role of Bob Newby. His casting is another of the show's many homages to their influences, as Astin previously portrayed Mikey in The Goonies, a 1985 film which has been noted by the Duffer Brothers as one of Stranger Things' major influences.