The cover artwork shows Prince Warwick sitting at a writing table.
"You'll win every bet with that coin."
Jessica and her best friend, Ryan, really enjoy magic tricks. They find the perfect HorrorLand souvenir in Jonathan Chiller's gift shop—a two-headed coin with mysteriously dark powers.
After an unlucky flip of the coin, Jessica and Ryan find themselves in a strange land being chased down by angry guards. HorrorLand was scary but this is much worse. Will they be able to escape with their heads still attached?
The book begins with Jessica Bowen and Ryan Chang exploring HorrorLand. Jessica is excited when she sees the HorrorLand magic shop. Jessica reveals that her father, The Amazing Billy Bowen, is a birthday party ventriloquist and magician; because of this, she is really interested in ventriloquism and magic. Inside the magic shop, the kids meet Mondo the Magical. Mondo shows the kids a coffin shaped box called the Forever Box. If someone is inside the box when it is closed, they disappear forever. Ryan volunteers to go inside the box, and Mondo agrees. When the box reopens, Ryan is gone. Mondo says that there is a secret door in the back of the box. When Jessica opens the door, she doesn't see Ryan. Mondo is very scared upon discovering this. Jessica volunteers to go into the box to look for Ryan.
Mondo closes Jessica in, and she falls down into a dark room. She sees a ladder and climbs out. When she emerges, she finds Ryan and realizes that she's in a gift shop. The kids meet Jonathan Chiller, the owner of the Chiller House shop. The kids find a coin that Chiller says will always land on heads. Jessica goes to buy it, but Chiller insists that she can pay later. Chiller wraps the coin and attaches a small Horror statue to the package.
The next day before school, Jessica sees the local bully, Boomer, picking on Ryan. Jessica convinces Boomer to flip a coin; if the coin lands on heads, he will let them go, but if the coin lands on tails, they have to give Boomer their lunch money for a week. Naturally, the coin lands on heads, and Boomer reluctantly lets the two kids go. When Ryan and Jessica go to pick up the coin, they become very dizzy, and, when they regains their focus, the kids realize that they are in a large field that they don't recognize. The kids begin walking. Jessica pulls out her cellphone with the intent of making a call, but her phone will not turn on. The kids find a wall, and they hear a horse's whinny on the other side. The kids hop the wall, and they realize that they are in front of a castle and several small shacks. The kids meet a blacksmith, and they try to ask him for help. However, the blacksmith becomes suspicious of the kids, and he calls for the guards. The kids run away. They find a battle axe, but, before they can use it, they are stopped by a group of guards who capture the kids in a net. The guards accuse the kids of killing the prince, and, because Jessica is holding a battle ax, the guards this as further evidence.
The kids are taken to a holding cell. The guards bring the kids before the Duke of Earle and the prince's wizard, Henway. Both of the men believe that the kids are guilty. They bring the children before the prince. The prince used magic to keep himself alive even though he no longer has a head. The prince writes down a message, and he demands his head back. Since the kids cannot reveal where the head is, the prince demands that they be executed.
The kids are brought before an executioner. Jessica decides to make a bet with the duke. The duke, a gambling addict, agrees. Jessica flips her coin, and she wins the toss because she knows how it will land. The duke sticks to his word and refuses to allow the kids to be executed. Henway suggests that the kids should instead be thrown into the dungeon.
While in the dungeon, Ryan manages to steal the keys of the guard who delivers food to the prisoners. The two kids frantically search for a stairway. A guard tries to stop them with his sword, but Jessica throws her voice in order to distract the hard. The kids run away. They find a closet filled with robes, so they decide to cover their conspicuous clothing. The kids then theorize the prince's head might still be near the castle, so they decide it is a good idea to look for it outside. They climb out of a window and look through some of the nearby shacks. One of the shacks is filled with hay, and the kids think that the head might be hidden there. Before the kids can truly search the room, a man approaches them. The man identified himself as Simon, the caretaker of the prince's rats. Since the prince owned hundreds of cats, he needed rats to feed them. The kids, unnerved by the man, run away. They run into the blacksmith again. The blacksmith forces the kids into the corner, and he says that he is going to report them to the guards again. However, Ryan becomes severely startled when he realizes that, beneath the pile of hay, there is a decapitated human head. The kids, wanting to return the head try to take it, but the blacksmith threatens to kill them if they do. Before the blacksmith can do anything, one of the horses from the stables begins to run away, and he is forced to stop it. The kids take the head and run. The kids turn themselves in to the guards. The kids are once again brought before the prince, but they present the prince with the head. The prince feels the head, and he uses his paper to tell them that the head is not his. The prince says that the head is most likely the head of one of his executed enemies. The kids are forced to once again run away. Jessica deduces that bogey haven't seen any cats, so Simon had to have been lying.
The kids run back to the rat shack. Inside the shack, Jessica finds the prince's head in a cloth sack. Before the kids leave, Simon returns. Ryan throws his voice to distract Simon, so the two friends escape. They once again are captured by the guards, and they are brought before The Duke of Earle and Henway. The two men reveal that they were the ones to decapitate the prince. Because the prince lost his head, most of his political power would have been divvied between the two assistants. The Duke says that the kids must be executed, but he succumbs to Jessica's offer of another coin toss. The Duke offers to flip the coin, and he does. Jessica is mortified when she sees that the coin has landed on tails. The Duke reveals that he swapped Jessica's coin for one of his own.
The kids are about to be taken away, but a booming voice suddenly projects from the sack cloth. The prince's head is talking. He reveals that he heard the assistants' confessions. The kids sprint to the Prince's room, but the prince is gone. They run onto the balcony, and the prince is there. The prince attaches his head, and he promptly sentences his two advisers to death. They are taken away. The prince, Prince Warwick, inspects Jessica's coin, and he notices that the face that appears on both sides of the coin is his own. The kids realize that the coin sent them back to help the prince. The prince tosses the kids their coin, but the coin falls to the floor. Both kids grab the coin at the same time, and they both feel the same dizzying sensation that they felt earlier.
Before long, the kids realize that they're back on the playground. The kids have a short period to celebrate before Boomer approaches them. Boomer demands their lunch money, but Jessica suggests that they flip a coin. Boomer agrees, and Jessica calls heads. Shockingly, the coin lands on tails. Jessica assumes that the prince swapped their coin for a regular coin.
That night, Jessica goes home. Even though she's broke, she's happy to be back. She notices that the Horror attacked to the wrapper that the coin came in is glowing. She is drawn towards it. Almost instantly, she is teleported back to Jonathan Chiller's gift shop. He says that it is time for her to pay.
- This book borrows elements from A Night in Terror Tower.
- Jessica's father is mentioned by name in the book: Billy Bowen.
- This book references Star Trek and Disney World.