Stargate SG-1: Valhalla: 14

SG-1 become enmeshed in a fierce battle straight out of Nordic mythology. Although unwilling participants SG-1 soon find themselves fighting with the Vanir against their ancient foe - the brutal giants of Jotunheim - and feasting with them long into the night. But when dawn arrives the team find themselves in a very different world. Although still at war the Vanir and Jotunheim have advanced a millennia and fight with weapons of the 18th century.