On the evening before their wedding, Katie and Mack make love under a full moon. Afterwards, Mack leaves to spend the night at his brother Paul's house. At Paul's, Mack's high school buddies surprise him with a bachelor party. Although they are nearly thirty, Mack's friends proceed to act out their adolescent fantasies with an expensive stripper. The party rages on until an uninvited guest appears. It is Charlie. Mack and Charlie had been best friends in college until Charlie committed the ultimate betrayal. He had slept with Mack's girlfriend--Katie. Now Charlie has appeared again, on the eve of Mack and Katie's wedding. Charlie claims that he has come to make peace with Mack. Although Charlie is skeptical, Mack begins to win him over. But has Charlie really come to bury the past or does he still love with Katie? In the end, no one is untouched by Charlie's revenge. Mack must pay a heavy price as he learns the true meaning of friendship--and love.