Superman enters a small town where every person falls asleep immediately upon arrival. What—or who—is trying to take over Brentville while everyone sleeps?

Superman: Clark drives Lois to the town of Brentville for a holiday, but upon arriving they find all the inhabitants asleep due to the effects of a strange gas. Lois also succumbs but Clark is immune, so he obtains a couple of gas masks at a fire station, then drives to a house on the outskirts of the town. The house is owned by Professor Hunter and his assistant Kolb. When Clark phones the sheriff of a neighbouring town for help, Kolb tries to knock him out, but Clark manages to get Lois and himself out of the house. As they are driving back to Brentville, they spot another car with four men wearing gas masks. Following the car, they observe the four men rob a bank. Superman captures the robbers, but when the police arrive they believe that Clark and Lois are part of the gang and arrest them. Clark persuades the police to drive to Hunter's house so he can confirm he called the sheriff from there, but on arrival they find only Kolb, who denies ever seeing them. The police lock Lois and Clark up in the house.

Changing to Superman, Clark breaks out and discovers that Kolb has been hired by a foreign spy, Baron Munsdorf, to obtain the formula for the sleep gas (which was invented by Hunter), and that they have Hunter tied up in the basement. Superman frees Hunter, then confronts Munsdorf who attacks him with a death-ray invented by Hunter. After Superman defeats Munsdorf, Hunter vows to turn over all his work to the US government.

Contents

1. The Hand of Morpheus
2. The Unconscious Tip-Off
3. Escape from the Mine
4. The Hidden City of Death
5. The fake Accident Racket
6. Vengeance Trail
7. The Missing Archaeologist
8. European War