The series focuses on the lives of the very unscrupulous world of the Greenleaf family. The patriarch, Bishop James Greenleaf (Keith David) is the charismatic (and quite manipulative) senior pastor and leader of Greenleaf World Ministries, which is based at Calvary Fellowship, a large megachurch in Memphis, Tennessee.
He is married to the villainous Lady Mae McCready Greenleaf (Lynn Whitfield), a woman who is very cold-hearted and cold-blooded and is quite power mad and very greedy.
James and Lady Mae have four children, three of which are still living, Jacob (Lamann Rucker), the eldest and ne'er do well son, married to Kerissa (Kim Hawthorne), an ambitious and controlling woman who is the head of the church school. Jacob cheats on Kerissa with the Bishop's secretary, Alexa (Kristen Erickson); Grace, called Gigi (Merle Dandridge), the older daughter, a former journalist and new pastor at the church, who came back to Memphis after an absence of 20 years to find out about the death of her twin sister, Faith; and Charity (Deborah Joy Winans), the youngest daughter. She is married to Kevin Satterlee (Tye White), a man who is also secretly gay, and serves the church as the minister of Music.
Grace is the mother of teenager, Sophia (Desiree Ross), whose father is a white man named Ray Fisher (Michael Rodrick). Sophia has a hard time dealing with things having being transplanted from Phoenix to Memphis. Jacob and Kerissa have a daughter named Zora (Lovie Simone), who tried to get Sophia into trouble at first. Later on, Zora and Sophia would bond and they would consider each other as sisters. Charity is pregnant with twin boys by Kevin.
Also involved in the family is Robert "Mac" McCready (GregAlan Williams), a wealthy and powerful mover and shaker in the Memphis community; he is the brother of Lady Mae and even MORE malicious than his sister. He also has a tendency to rape little girls, which is what might have happened to Faith. He is also accused of molesting his nieces, Zora and Sophia.
Oprah Winfrey has a recurring role as Lady Mae and Mac's black-sheep sister, Mavis. Mavis, who runs a blues club, is nothing like her more sinister siblings. She is perhaps the closest confidant for her niece, Gigi. At one point, she produced a paper that proved that her brother was a child molester. This caused him to be jailed.
Other characters include Melisse (Terri J. Vaughn), the head housekeeper at the Greenleaf Mansion; Noah Kendall (Benjamin Patterson); the mansion's estate manager; church security chief, and the former boyfriend of Gigi (they were childhood sweethearts); Isabel (Anna Diop), a teacher at the church school who is now engaged to Noah, and hates the idea of Gigi being back; However, Isabel gets mad and leaves Noah, knowing that he will never fall out of love with Gigi. She does end up returning in the first season finale.
Family secrets hidden underneath the facade of a highly moral and "Christian" power family who run a huge megachurch, is one of the main focuses of this series.
In the first season finale, Grace gets up in the pulpit at Calvary Fellowship, the Memphis megachurch that serves as the headquarters of Greenleaf World Ministries, and, much to the disgust and dismay of James and Lady Mae, and delivers a sermon that denounces sexual violence and rape. Lady Mae confronts Mavis about her life, and Mavis retaliated by revealed that her sister had known about her own daughter dying; Sophia going back to Phoenix with her father, and her saying a good bye for now to her mother and her family; and then a vengeful Mac, intent on making his family suffer, coming up to Greenleaf Mansion, with a police escort, on their way to have Bishop James arrested.
In the second season, Williams and Simone become regular members of the cast, after having been recurring in the first season as Mac and Zora.
Charity lost one of the twins during the fight she had with Kevin and is trying to be careful towards losing the other child, she however induces labor and gives birth to a healthy baby boy. Jacob leaves Calvary to take a job at Triumph Church, a rival church which drives a wedge between him and the family; Lady Mae makes a desperate attempt to try to save her husband from being jailed, and she still argues with Gigi because of her crusade against Domestic and Sexual violence, seeing this as a slap in the face against her and her own hidden secrets, however, she unbends a bit and begins to try to understand Gigi. Sophia returns to Memphis from her time in Phoenix with her father, and feeling more at home in Memphis after being away. Lady Mae also denounces her brother for the things he had done to her family, and tells him that he is not family to her anymore. James is revealed to have killed Basie's father, which explains the animus between Calvary and Triumph.