“Thor’s Hammer” is episode ten of season one of Stargate SG-1.
Daniel has come up with a theory that suggests that there were two different types of gods, the bad tyrannical gods, the Goa’uld, and good gods, which were another alien race who were enemies of the Goa’uld.
Daniel’s theory is that the Viking gods were possibly those aliens, and that Thor was a protector of mankind. Teal’c knows the stargate address of a world forbidden to the Goa’uld where the symbol of Thor’s Hammer was seen, and SG-1 goes there. On arriving through the stargate, the team is scanned and Teal’c vanishes, with Colonel O’Neill when the latter grabs him. It turns out that the beam transported Teal’c and O’Neill somewhere.
Daniel and Carter try to find out what has happened from the outside whilst Teal’c and O’Neill are trapped inside. Getting out isn’t too difficult – unless you have a Goa’uld larva in you, like Teal’c does.
This episode sees the Asgard appear for the first time, although not in their true form, who later play a substantial role in the series.