Like the title suggests, Topdog/Underdog (published in 2001) is a play about competition, reversals, and mirror images that reflect the true self. The idea that became Topdog/Underdog can be found in one of Parks's earlier plays, The America Play (1995), which features a gravedigger named the Foundling Father whose obsession with Abraham Lincoln leads him to find work in a sideshow. Like Link in Topdog/Underdog, the Foundling Father applies whiteface, models several different types of fake beards, and sits in a chair awaiting visitors who pay to assassinate "Abraham Lincoln" with a cap gun. Though the Foundling Father and Link hold the same job, any similarities between these two protagonists end there. Regardless, Parks's fascination with history, especially personal history, and the ways in which illusion can reveal identity makes for riveting drama.

Topdog/Underdog tells the story of two brothers, Lincoln and Booth, who, abandoned by first one parent and then the other, have had to depend upon each other for survival since they were teenagers. Now in their thirties, the brothers struggle to make a new life, one that will lead them out of poverty. Lincoln, a master of the con game three-card monte, has abandoned a life of crime for a more respectable job impersonating Abraham Lincoln at an arcade. Booth, on the other hand, earns his living as a petty thief, one who wishes to emulate his older brother's success by learning how to "throw the cards." Throughout the play, the brothers compete against each other, vying for control. At any given moment, one may yield power over the other, only to relinquish it in the next. Hence, Topdog/Underdog reveals a topsy-turvy world in which Lincoln and Booth live, a chaotic world that is as dangerous as it is illusory.