With the deep-sea base on the brink of destruction, Mia is getting closer and closer to discovering the culprit behind the murder of her father. However, as the crew struggles to survive, revelations of the Dept. H project comes to light that will alter the lives of the crew if they survive. Life on the surface hangs in the balance as Mia races against time. This omnibus edition collects issues #13-#24 of Dept. H, as well as a sketchbook section and bonus material!