I do not want to confuse anyone with long list of characters, so I am going to break down the roles of each character
Natalie Porter - FBI agent solving a murder case.
Harry Styles - male escort, hot, mysterious, possibly involved in the murder
Norah Smith - Natalie's older sister who is married to Austin
Austin Smith - Norah's husband, lets Natalie live with them
Rylan Smith - Norah and Austin's son, Natalie's favorite person in the world
Zayn Malik - FBI agent working with Natalie on the case, they are good friends but Zayn likes her more than a friend.
Niall Horan - Natalie's ex boyfriend, but he still is really good friends with her, he knows why she is depressed and can't help but to take the blame.
Zebula - a lady who lives downstairs in their apartment, she is a medium (can talk to the dead) and tries to help Natalie.
Jacob Maxx - owner of the male escort and strip club, strict on his employees, hiding something.
Teresa Maxx - the wife of Jacob, she manages the escort business.
Carl Adams - a poor guy who tries to be friends with Jacob, he knows the gossip on everything. in love with Amy
Amy Nelson - works for Jacob at his strip club, one of the eldest women that works there.
Bella Thorne - actor, dancer, singer, very famous! gets cast onto a new show until something terrible happens...
Liam Payne - Bella's boyfriend, also famous!
Louis Tomlinson - a good friend of both Bella and Liam, tries to console Liam in his hard time of grief...but he is also hiding something
That's basically it, if you need more information or found something unclear just comment! I tried not to have any spoiler alerts during the description of the characters.