Frankenstein, Agent of S.H.A.D.E., tome 2 : Secrets of the Dead

The mysterious organization known as S.H.A.D.E. protects the world from its most dangerous supernatural threats. But what happens when the threat comes from within S.H.A.D.E. itself? Frankestein and his Creature Commandoes must investigate suspected double-agents in their own field offices. Their first stop is the Untropolis--an exact copy of Metropolis that floats upside down in the 4th Cloud above Superman's hometown. Will Frank and company be able to stop the threat to S.H.A.D.E. before the organization gets capsized from the inside?