Mark Watson is the pampered son of a rich family who is about to attend Harvard Law School along with his best friend Gordon. Unfortunately, his father's neurotic psychiatrist talks his patient into focusing on his own happiness instead of spending money on his son. Faced with the prospect of having to pay for law school by himself, Mark decides to apply for a scholarship, but the only suitable one is for African Americans only. He decides to cheat by using tanning pills in a larger dose than prescribed to appear as an African American. Watson then sets out for Harvard, naïvely believing that black people have no problems at all in American society.
However, once immersed in a black student's life, Mark finds out prejudice and racism truly exists. He meets a young African American student named Sarah Walker, whom he at first only flirts with; gradually, however, he genuinely falls in love with her. In passing, she mentions that he received the scholarship she was in the running for at the last minute. Due to this, she not only has to handle her classes but work as a waitress to support herself and her young son George.
Slowly, Mark begins to regret his decision as he continues to experience problems because of his skin tone. He gets arrested by a cop who assumes that he is a thief because he is driving an expensive car, is put on the receiving end of many hurtful racial stereotypes by white people and finds himself subjected to sexual harassment by his landlord's daughter, Whitney, who is eager to explore what she perceives to be the "exotic" thrill of sleeping with a black man.
After a chaotic day in which Sarah, his parents (who are not aware of his double life), and Whitney all make surprise visits at the same time, Mark drops the charade and publicly reveals himself to be white. He is surprised to find that many are willing to forgive him for the charade after considering his reasons for doing so, but Sarah is furious. Mark has a private conversation with his professor. He has learned more than he bargained for, admitting that he still doesn't know what it is like to be black because he could have changed back to being white at any time.
Because Mark must forfeit his scholarship, his father agrees to loan him the money for school, but with exorbitant interest. He goes to Sarah and begs for another chance, to which she agrees after Mark stands up for her and George when two male students tell a racist joke in front of them.
