Published Jan 1971 by Marvel.
"The Monster's Secret!" Script by Stan Lee. Pencils by John Romita. Inks by Joe Sinnott. Cover by John Romita and Joe Sinnott. Mister Fantastic has a double crisis on his hands! The Invisible Girl needs help in her fight against the mysterious monster on the streets! While at the same time, Reed's experiment to change the Thing back to flesh-and-blood Ben Grimm reaches a critical stage! The leader of the FF decides to help his wife and leaves Johnny to supervise the experiment! After the Human Torch cools down the high-tech testing equipment, he joins Reed and Sue in the battle vs. the powerful energy creature (aka Larry Rambow)! But while three-fourths of the Fantastic Four are fighting in the city, what's going on back at the Baxter Building...with the unconscious Thing? 32 pages Cover price $0.15.