3-Card
Lincoln hustles his brother in the final scene of the play for his $500 inheritance. Ironically, by playing his brother for a fool he gets himself shot by Booth, who is unpredictable and dangerous.
Love
Booth tells his big brother that Grace wants him to marry her and have a baby with her. Ironically, Booth has just killed her for breaking the relationship off with him.
A Name
The brothers were named by their father out of an ironic turn of humor. Unfortunately, the irony of their names comes to be prophetic as Booth kills his brother.
Brothers
Lincoln is staying with his younger brother's apartment in order to get back on his feet. Ironically, Booth slept with Lincoln's wife and is one of the primary reasons for their divorce.
The Hustle
Lincoln was the best 3-card player on the east coast and was making money hand over fist with the hustle. Ironically, the game is what gets his friend Lonny killed when they hustle someone who doesn't want to pay.