A Scotsman named Gerald MacTeam (Richard Carlson) abruptly breaks off his engagement to pretty Kitty (Veronica Hurst) after receiving word of his uncle's death. He inherits a mysterious castle in the Scottish highlands and moves there to live with the castle servants. Kitty refuses to accept the broken engagement and travels with her aunt (Katherine Emery) to the castle. When they arrive, they discover that Gerald has suddenly aged and his manner has changed significantly.
After a series of mysterious events occur in both the castle and the hedge maze outside, they invite a group of friends, including a doctor, to the castle in the hopes that they can help Gerald with whatever ails him. Although the friends are equally concerned by Gerald's behavior, they are at a loss to its cause. One night, Kitty and her aunt steal a key to their bedroom door (which is always locked from the outside) and sneak out into the mysterious maze. There they discover Gerald and his servants tending to a frog-like monster. The monster panics upon seeing the strangers and runs back to the castle, hurling itself from a top-story balcony.
At the end, Gerald explains that the amphibious creature was the actual master of the castle and that he and his ancestors were merely its servants. The death of the creature releases him from his obligation and he is able to return to a normal life.
What does the monster hurl itself off of?
top-story balcony