Space Sentinels is a Saturday morning animated series produced by Filmation which debuted on the American NBC network on September 10, 1977 and ran for thirteen half-hour episodes. The series has been called "ahead of its time" due to its racially diverse cast of main characters. In this series, the Roman mythological figures Hercules and Mercury are joined by Astrea, a character created specifically for the series, to form a superhero team to protect mankind. The complete series was released on Region 1 DVD on August 22, 2006, along with the complete series of The Freedom Force..