One of American literature’s greatest courtroom dramas is generating some legal theater of its own. To Kill A Mockingbird author Harper Lee is suing her former lit agent’s son-in-law, Samuel Pinkus, and companies he allegedly started for failing to protect the Pulitzer-winning novel’s copyright. Lee, 87, alleges that Pinkus took advantage of her failing eyesight and hearing and assigned the copyright to himself and a firm he operated after his father-in-law, Eugene Winick — who had repped Lee since the book’s publication in 1960 — became ill 10 years ago. The author, who lives in rural Alabama, filed suit in Manhattan federal court and is seeking return of the copyright and unspecified damages. The 1962 movie adaptation of Mockingbird was nominated for Best Picture and seven other Academy Awards and won three, including Best Actor for Gregory Peck’s legendary performance as Atticus Finch. The lawyer who becomes a pariah in his small Southern town as defends a black man accused of raping a white woman was hailed by the AFI in 2003 as the greatest film hero of all time. Last year President Obama introduced the film before a 50th anniversary screening at the White House.