The Three Investigators in The Secret of Terror Castle

13 year old kind-hearted Sonja arrives at a tiny village together with a company of bandits. But there is a curse on the village. A long time ago, the King’s only daughter Goldhair disappeared while searching for the Christmas Star. The Queen died of a broken heart, leaving the shattered King all on his own. From that day on, the King cursed the Christmas Star, thereby causing darkness and grief to descend upon the land. However, an old sage has revealed that Goldhair is still alive, and will return only if the King finds the way back to the Christmas Star. Ever since, the King has been searching for the Christmas Star every Christmas, but all in vain.

As the Twelfth Doctor nears regeneration, he stumbles on his first incarnation, also refusing to change. It takes a captain, a glass avatar and a familiar face to convince the Doctors the universe still needs them.

The hobby detectives “The Three Investigators” want to take a little break. So they take advantage of an offer from Peter's father, who has accepted a job in South Africa and wants to take the detectives there. But Jupiter, Peter and Bob wouldn't be the three investigators marks feared by the criminal world if they just lounged around in the sun on their vacation. So it's no wonder that the clever boys soon have their next case to solve...

A couple is going through marital troubles made worse when a previously unknown grandson shows up.

During the summer vacations, the three friends are about to take a trip together to Romania, where they are allowed to complete an internship on the film set of "Dracula Rises", arranged for them by Peter's father, who is responsible for the special effects during the filming. No sooner do they arrive in Transylvania than mysterious events begin to pile up at Countess Codrina's old castle, which serves as the original setting for the film. The three detectives want to find out what all this may have to do with a boy who has been missing for over 50 years, a mysterious brotherhood and an enigmatic undead. Soon, not only the filming and Peter's relationship with his father are at stake, but also the friendship of the three investigators.

A group of researchers in Antarctica are abducted by a platoon of masked soldiers and dragged into a hidden continent in the center of the Earth. There, they discover that surviving Nazi soldiers are plotting an invasion of Earth to revive the Third Reich.

It was Peter's idea to invite his friends on a joyride on Justus' birthday of all days. In pouring rain, a car breakdown forces the three detectives to seek refuge at the creepy "Blackstone" castle. When lightning knocks out the power line, the three investigators are stuck for good. It soon becomes clear to the three junior detectives that the lord of the castle, Count Gallagher, is a real chess fanatic. But not only that - the old castle makes a spooky impression and then there is Moe, the count's sinister servant. What is it about the chess pieces on the dilapidated, centuries-old chess table that seem to move by themselves, move after move, as if by magic? Is the old building really haunted? The first detective is immediately hooked and senses a new case, only Peter wants to run away. It soon becomes clear to the three investigators that this is about much more than just a game of chess...

Following the death of his father, a suburbanite runs away from home and winds up on Chicago's South Side. After being mugged, the boy befriends a young hustler and, after stealing a gangster's car, the two embark on an adventure down south in search of the hustler's estranged father.