The characters are vital. The detective draws the readers in with their investigations. The suspects' actions and motives keep the plot interesting. Also, other characters like informants help the detective. All these characters together make the mystery novel engaging.
The cast in a mystery novel often includes the detective, who is the central figure in solving the mystery. For example, Sherlock Holmes is a very famous detective character. Then there are usually suspects, each with their own motives and alibis. And there might be sidekicks to the detective, like Dr. Watson for Holmes, who assist in the investigation. There are also victims, whose situations set off the whole mystery - whether they are murdered or have something valuable missing.
Well, there are often detectives. They are smart and observant, like Sherlock Holmes. Then there are the suspects, who have secrets and motives that need to be uncovered. And victims, whose fates drive the mystery. There might also be sidekicks to the detective, providing support and sometimes comic relief.
There are two main characters in the 'Frankenstein mystery novel'. Victor Frankenstein is a very important character. He is the one who dares to cross the boundaries of nature and create life. His actions and decisions are at the core of the mystery. Then there is the monster. It is a complex character. It is born into a world that doesn't accept it and its struggle and actions are what make the story so mysterious. There are also some secondary characters like Frankenstein's family members, but the two main ones are Victor and his creation.
In the 'Mystery of the Emblem Novel', there could be a young protagonist who stumbles upon the mystery of the emblem by accident. There might also be an old sage - type character who has some knowledge about the emblem's history but is reluctant to share it all at once. And perhaps there's a villain who wants to use the emblem for their own malicious purposes, like taking over a kingdom or something similar.
There could be a variety of characters. There might be a strong and resourceful man who is good at building shelters and finding food. There could also be a woman with a kind heart who takes care of the others emotionally, and perhaps a child who brings out the protective side of the other characters.
I don't know the specific main characters in 'the mystery guest novel' as there's not enough information given. But usually, there would be the mystery guest themselves, and perhaps a protagonist who tries to figure out the mystery around the guest.
The mystery surrounding them makes them interesting. For example, a character with a secret past that might be related to the crime. Their motives are often unclear at first, and that draws the reader in.
They are developed in multiple ways. Some characters' pasts are slowly uncovered, like if a suspect has a history of being wronged which could be a motive for the crime. The relationships between characters are also crucial. For instance, if two characters are rivals, it might influence how they interact during the mystery. And their dialogue plays a big role. A character who is nervous might stutter or give short, evasive answers.
I don't know the exact main characters as I haven't read it. But likely, the doctor is one of the main characters. There could also be a nurse or a patient who plays an important role in the story.