HBO has shown new trailers for the fourth season of Game of Thrones and the upcoming first season of half-hour comedy Silicon Valley. Game of Thrones third trailer shows the characters of George R. R. Martins low-fantasy world in a more subdued mood than seen in previous trailers, as they mull their secrets and burdens, and consider who they can trust after the bloody finale to the shows third season. Silicon Valley — from Beavis and Butt-head creator Mike Judge — is an altogether lighter affair, centering on the lives of six programmers trying to become successful in northern California. Both shows will air on HBO on April 6th.