I am trying to write a murder mystery set in an alternate earth around the Victorian era. Six young women are selected to join the Queen’s court, which is practically a death sentence. I want every character to have a secret profession or secret that could get them killed if the wrong people found out. So far I’ve covered 2 of the characters. One dabbles in poison making, the other is taking the place of her newly deceased sister. I want to give the others something dark to hide. This is a short overview of the characters. 1.) Eleanora “Ella” joined to save her family from falling to ruin because of bankruptcy. 2.) Adeline’s family is close to the royals and has always had at least 1 family member as a royal advisor. 3.) Amity has a secret relationship with a guard at the palace. 4.) Lottie dabbles in poison and is the youngest of the six. 5.) Celeste is the oldest and is closest with the Queen. 6.) Evelyn is taking the place of her sister who committed subside to escape the Queen’s Court. Any ideas?
You have most of it laid out right here. I would just start writing about the character with the simplest trajectory - so probably Amity - and see how the others unravel themselves from there. I would say that Celeste does not have much of a trajectory. What's her secret? You seem to know everybody else's secret or at least drama. Adeline would have to have a corrupt family member - something like that. Someone who she knows is corrupt but covers for. Perhaps that's her secret. Let me know if this is helpful.
Eleanora is a laudanum addict. Adeline is the king's illegitimate daughter. Amity is not virgo intacta and all the queen's ladies are supposed to be chaste. Lottie provides herbs to girls who find themselves in delicate conditions Celeste is a lesbian. Evelyn practices black magic.
Take a look at Story Genius by Lisa Cron. She lays out a method of creating back story, that can create both solid characters and tge story itself.