Gwendy's Button Box is a novella written by Stephen King and Richard Chizmar. It was first announced by Entertainment Weekly on February 28, 2017. It was released on hardcover on May 16, 2017, and on paperback on October 31, 2017.
The story begins in 1974. At age twelve, during the summer before she is due to start Middle School, Gwendy starts exercising in an attempt to lose some weight, wanting to get rid of her nickname “Goodyear” (after the Goodyear Blimp). Every day, she runs up and down the Suicide Stairs at a cliff side.
One day, when she reaches the top, she is approached by a man dressed all in black. The man, who names himself Richard Farris, who invites her to palaver. He gives her a small, mahogany box, with 8 buttons on top and two levers on the sides. Six of the buttons represent the continents North-America, South-America, Europe, Asia, Africa and Australia. The other two, a red and a black one, have no specific destination, but Gwendy is told the black one is the most dangerous of all, and the red one is the only one she can use repeatedly. Pulling the levers makes the box spit out tiny, magical chocolate animals, and silver dollars in mint condition respectively. After their talk, Farris disappears, though Gwendy will have several nightmares about his black hat.
In the years that follow, Gwendy keeps the box hidden for everyone. Her life takes several turns for the better thanks to the chocolates; she loses her excessive weight, her eyesight improves to the point she no longer needs glasses, and she gradually grows into a gorgeous teen. She also becomes a grade A student and excels in athletics. Her parents, whose marriage was falling apart, both stop drinking and get to love each other again. The silver dollars ensure that she can pay for her college education. But the secret of the box weights down on Gwendy, and her good fortunes eventually drive a wedge between her and her best friend Olive.
One day she can no longer resist the urge and pushes the red button, making sure to focus on the South-American country of Guyana to try and limit the damage. This triggers a tragic event in which a cult leader named Jim Jones commits suicide and inspired 900 of his followers to do the same. Among the deaths are multiple children and babies.
At age 17, Olive commits suicide by jumping off the Suicide stairs. Torn by grief, Gwendy uses the red button again to destroy the stairs and part of the cliff. She is barely able to attend Olive's funeral, but carries on with her life the best she can. She meets a man named Harry Streeter, and falls in love with him. She slowly grows tired of the box and her dependence on it. She stops using the magic chocolates, even though this causes her to gain a few pounds and her grades slightly drop, and tries to forget about the box altogether.
As graduation week approaches, Gwendy is attacked in her room by Frankie, a boy whose advances she once rejected. He has found the button box and the silver dollars. Harry tries to defend Gwendy, but is fatally injured when Frankie hits him with the box. Frankie then proceeds to attack Gwendy with a knife. Gwendy is stabbed in her foot, but manages to get hold of the box and uses the red button to dispose of Frankie.
Gwendy loses part of her foot due to Frankie's attack, but otherwise does fine. She goes to college, taking the box with her. She still occasionally eats the chocolates, and uses the silver dollars to pay for her education. She takes up the aspiration to become a writer.
Then one night, 10 years after she got the box from him, Gwendy encounters Richard Farris again. He congratulates her for taking good care of the box. At his request, Gwendy finally admits what happend the night she used the box against Frankie; he litterally rotted away the moment she pushed the button. She then made his body disappear, so the authorities would never suspect her of murder. Farris in turn consoles Gwendy with the news that the Jonestown massacre and Olive's death were not her doing, and that her self control to not use the box has prevented several tragedies from happening. He takes the box back and disappears into the night. Gwendy stays behind with one final silver dollar, and Farris' promise that she will become a famous writer.