Almost Famous: The opening credits of the film are an homage to the opening credits of To Kill a Mockingbird, and in the first scene, William and his mother are discussing the movie. Later, when his mother takes William to the Black Sabbath concert, she reminds him he wanted to be Atticus Finch when he was younger.
Vanilla Sky: Dr. McCabe, the psychiatrist treating David, is somewhat of a father figure in the vein of Atticus Finch. Later, when David learns everything involving McCabe was All Just a Dream, we find out To Kill a Mockingbird was one of his favorite movies growing up - it's the movie the prison guard is watching on TV - it makes sense David would imagine his psychiatrist being an Atticus Finch figure.
About Scout: Sam thinks the talk show Scout's watching is too depressing and changes the channel to To Kill a Mockingbird. He assumes Scout was named after the movie's protagonist, but she tells him she was actually named after Demi Moore's daughter.
In a flashback in The Good Doctor episode "Zero Point Three Percent," Shaun gives Steve a copy of the book for his birthday. In the present day, he reads part of the book to Evan.
Power Rangers Jungle Fury: "Path of the Righteous" opens with Dominic reading the book, and he summarizes it as how one man is willing to stand up for his beliefs against all odds. As he struggles with being the only one who believes Jarrod can be redeemed, Casey takes this to heart.