This takes place during the John Byrne era, right after Fantastic Four issue 238.
The Fantasti-Car dropped down into the roof of the Baxter Building. The members of the Fantastic Four, along with trainee Frankie Raye, were returning from meeting Ben Grimm's Aunt Petunia in Arizona, and were in a mood to enjoy a bit of piece and quiet.
When the craft finally docked, the members got out. The FF's leader, Reed Richards, stretched his arm to the door, opening it. Richards had gained his powers years before, but still marveled at his ability to stretch any part of his body. He stepped out of his section of the Fantasti-Car and stretched his other arm around his wife.
Susan Storm Richards blushed as Reed pulled her close and kissed her deeply. Without realizing it, Sue used her power and turned invisible. Neither Reed nor Sue realized she had, because they were intently kissing each other.
But the other members of the FF saw the slip. Sue's brother, Johnny Storm, smiled and turned to his girl friend, Frankie Raye. Together, they both turned their bodies to flame and rose in the air, kissing each other through the fire.
It took the last member of the FF to bring them all back to earth. "Awright, you lovebirds. Git visible, git on the ground, and git a room." The deep voice of the Thing rumbled through the hanger. Sue realized she was invisible and popped back into view. She and Reed broke apart and smiled at their friend.
"Ben Grimm, you softie," Reed said, using The Thing's name. "You're just upset because Alicia isn't here to kiss you."
Johnny threw a fireball at Ben. His rock-like exterior took the fireball in stride, but he turned his head up at the Human Torch. "You little punk, git down here and do that!" Ben growled.
"No way, Ben," Johnny said. "I value my life too much. Besides, Frankie and I are heading out. See you all later." With a pair of fire trails following them, the two torches flew out of the hanger through the still-open roof.
The three companions entered the elevator and dropped to the science level. There Reed got off the elevator, pulling the Thing with him.
"I have something in the lab you might want to see," Reed said to Ben.
"Aw, not another disappointing attempt to change me back to human," Ben grumbled. But he also left the elevator, allowing Sue to ride alone down to the living level. Ben had recently been "devolved" from solid bricks to a melted-rock skin by Reed and Sue's son, Franklin Richards. Now that he was at a stage he had been when they first became the FF, Reed felt certain he could reverse the changes permanently.
Sue, with no taste for science, stepped off the elevator on the 35th floor of Baxter Building. She slipped down the hall and peeked into the bedroom of her son, Franklin Richards. Franklin was playing with her babysitter, the aforementioned Alicia Masters.
Alicia, although blind, had hyper-sensitive hearing, and she could tell Sue had entered the room. She whispered, "Your mom is here," to Franklin, releasing the boy so he could fly into his mother's arms. Franklin was 5, and would be entering school in the fall. But for now, he stayed in the Baxter Building, where Reed's instruments could gauge his ever-changing powers.
Two floor higher, Reed and Ben entered his lab. Reed stretched to a slow-burning bunsen burner and took a test tube off the heat. He took a second tube off a rack and added a few drops to the first one.
"Ben, please move that Molecular Isotope Dispersement and Analyzer Seat two feet to the right, would you?" Reed said.
Ben looked at the large metal chair surrounded by metal rods, plastic wires and a large cone over the seat. He lifted the seat, then laughed.
"What's funny, old friend?" Reed said.
"This Seat do-hickey, Stretcho," Ben replied. "You're losing your touch. It can't weigh much more than five tons. I kin remember when your machines were all in the 20-ton range."
"Miniaturization helps keep the weight down. Plus, I allocated several dispersement nodules the same relative space, meaning that ..."
"Meaning that I don't care, I just hope it works," Ben interrupted.
Several minutes later, Ben was sitting in the middle of the MIDAS machine, drinking the formula Reed had given him. He started glowing, and Reed turned several dials on the MIDAS. As Ben continued to glow, the MIDAS sucked the energy into itself. Slowly, Reed could see his best friend changing. The rocky exterior was fading, being replaced by a man with brown hair and craggy features.
When the machine shut down minutes later, it was not the Thing that emerged. It was Ben Grimm, holding his now-too-large shorts in one hand. Reed smiled. His experiment was an apparent success.
"Looks like you'll need to get someone else to move your machines, Reed," Ben said.
"Not at all," Reed said. "Concentrate, and you should be able to change back to the Thing."
Ben's forehead furrowed, and in a mater of moments, the rocky exterior of the Thing had once again covered Ben's body. "Now, change back," Reed ordered. The Thing thought hard again, and the scales vanished, leaving a now-naked Ben in the middle of the lab, his shorts a heap on the floor.
"I don't know how long the changes will last, so be careful changing back and forth," Reed warned. "To be honest, it will be better for you if you remained rock-like most of the time, changing back for special occasions." Ben merely nodded his head, and resumed his Thing form.
At that minute, the lab door burst open and Alicia Masters walked into the room. She rarely used a cane, having become accustomed to most of the rooms in the Baxter Building headquarters of the FF. She walked into the room and said, "Ben? Did Reed's experiment work?"