Ragnarok!

August 1968, New York City. Adman Stanley Arthur Havelock's client presentation-to-be has been derailed by a femme fatale competitor. As he scrambles toward his meeting deadline, things can't get any worse—until they do and he finds himself knee deep in snow on a world called Asgard. Here, because of his ancestry, he is pressured to lead an expedition to "neutralize" a mountain-size beast of destruction known as Ragnarok. Along with a scheming Loki, an angry female Merlin, a mythological ymer, a constantly protesting Myrtle Ann Loomisjohn (the femme fatale mentioned earlier), and two bards to document his deeds, Havelock braves a closed-canyon ambush, three witches that might have been vacationing from Macbeth, an invisible troll, a very large and hungry worm, and some dangerous aviators called hrungers. Along the way, they obtain as their main transport Kitty Hawk, a big-box-toting gryphon, who takes her catnaps and feedings at the most inappropriate times. At the quest's end, of course, is Ragnarok. Deep within the mountain known as Cloud Kisser, he is unaware of the approaching challenge. It's Havelock's unsettling forecast that the monster has nothing to worry about.