Sure! Here is a plot for a whodunnit murder mystery with six subjects:
Title: "The Case of the Missing Heirloom"
Characters:
1. Emma Watson - the victim, a wealthy socialite known for her love of expensive jewelry and her tumultuous relationships with her friends
2. Jake Smith - Emma's ex-boyfriend, a successful businessman with a reputation for being jealous and possessive
3. Samantha Jones - Emma's best friend, a fashionable influencer with a secret gambling addiction
4. Tom Williams - Emma's current boyfriend, a charming actor with a history of infidelity
5. Rachel Lee - Emma's personal assistant, a hardworking and ambitious woman with a troubled past
6. Detective John Doe - the investigator assigned to the case, a no-nonsense detective with a talent for solving complex mysteries
Plot: Emma Watson is found dead in her mansion, with one of her prized heirloom necklaces missing from her jewelry box. Detective John Doe is called to the scene to investigate the murder. He begins by questioning the people close to Emma, starting with her ex-boyfriend Jake Smith. Jake claims to have no motive for killing Emma, but Detective Doe isn't convinced - he knows that Jake had a history of being possessive and jealous of Emma's relationships.
Next, Detective Doe interviews Samantha Jones, Emma's best friend. Samantha initially seems to have a solid alibi, but further investigation reveals that she had a gambling problem and was in significant debt. Could she have killed Emma to try and get her hands on some of her valuable jewelry?
Tom Williams, Emma's current boyfriend, is also a suspect. He has a reputation for being a ladies' man and had been seen flirting with other women at a party the night before Emma's death. Could he have killed Emma in a fit of jealousy or to be with someone else?
Rachel Lee, Emma's personal assistant, is the next person to be questioned. She seems to have a solid alibi, but Detective Doe can't shake the feeling that she's hiding something. He starts to dig into her past and discovers that she has a criminal record for embezzlement. Could she have killed Emma for her money or valuable possessions?
As the investigation continues, more and more evidence starts to surface, pointing to each of the suspects. Just when it seems like the case is starting to come together, a shocking twist is revealed - Jake Smith, Emma's ex-boyfriend, was seen on surveillance footage breaking into Emma's mansion the night of the murder. He confesses to the crime, claiming that he was driven to desperation by his love for Emma and his belief that she was planning to leave him for Tom Williams.
As the case is closed, Detective Doe is hailed as a hero for solving the mystery. But he knows that in the world of murder investigations, nothing is ever as simple as it seems.