Thorskald was an archaeologist who, following earlier work by Jastro, explored various locations in Iceland looking for remnants of the lost continent of Atlantis east of the former dig site of his predecessor. During his work, Thorskald descended into a crater where he unearthed an Atlantean horned idol but froze to death
With Marcus Brody was unable to contact Thorskald, Indiana Jones and Sophia Hapgood sought out the archaeologist in 1939, in order to understand the Nazi interest in Atlantis, and the pair found his corpse clutching the idol. Jones speculated that Thorskald had climbed down into a underground chamber, gotten soaked by a geyser, then was frozen solid as the temperature dropped.
Behind the scenes
Thorskald appears in the comic adaptation of Indiana Jones and the Fate of Atlantis, the LucasArts video game which was actually released the year after its story was adapted. In the game, Thorskald's role was fulfilled by Bjorn Heimdall, a different character who is seen alive and well before suffering a similar fate to his comic counterpart having just exposed an eel figurine.