From the back of the book:
The military has come to New York in full force after a strange mystical barrier has erected itself around the island of Manhattan, transforming the teeming metropolis into a Hyborean realm of barbarians and magic. In Washington DC, there is an emergency meeting with National Security at the White House. There, Valerie Cooper briefs those gathered of the situation going on in New York. She explains that anyone who crosses the mystical barrier into the city is transformed into a barbarian from a bygone era with no memory of their previous life. However, those who stumble out of the area are restored to normal. Intelligence has gathered that an evil sorcerer named Kulan Gath is responsible for the spell. Attempts to contact the Avengers and the Fantastic Four have failed, however Val confirms that a number of super-humans have been spotted active in the city. All of them appear to have been transformed.
Val hopes the super-human community trapped within the mystical barrier can resolve their problem.
Who is this Kulan Gath? What does he want, and why has he transformed all of Manhattan?
More importantly, who can stop him?
Can you navigate Hyborean Manhattan, thwart Kulan Gath’s plan, rescue the citizens and return the island to its proper state?