Stargate

Everything set around the Stargate, an ancient ring that opens wormholes to other worlds. It starts with Roland Emmerich's 1994 film, continues in Stargate SG-1's ten seasons, then branches into Stargate Atlantis and Stargate Universe. The Ark of Truth and Continuum (both 2008) follow SG-1's finale, Stargate Origins (2018) is a prequel set in 1939, and Stargate Infinity is an animated series that the live-action shows treat as outside the main continuity. In release order: Stargate (1994), Stargate SG-1 (from 1997), Stargate Infinity (2002), Stargate Atlantis (from 2004), Stargate: The Ark of Truth (2008), Stargate: Continuum (2008), Stargate Universe (from 2009), Stargate Origins (2018).