When Andrew Makepeace Ladd III accepts an invitation to Melissa Gardner’s birthday party, and Melissa writes a thank-you note to ask just why he got her “The Lost Princess of Oz” (answer: she looks like a lost princess), a romantic friendship and correspondence destined to last for almost half a century is born. Both from affluent, East Coast families — Melissa has more money, but Andy has better parents — the friends communicate with each other through angst-ridden boarding school experiences, European adventures, failed marriages, and the ups and downs of career. Over the course of their lives, Andy and Melissa’s relationship goes through many changes, as the sometimes-sweethearts/sometimes-friends go through periods of estrangement, and the intense, clandestine affair which will accelerate Melissa’s emotional breakdown. Despite the painful differences which will ultimately tear them apart, they remain each other’s most trusted confidante, and are “true lovers” on paper, if not on the earth. A.R. Gurney’s Love Letters is a tender, tragi-comic, and nuanced examination of the shared nostalgia, missed opportunities, and deep closeness of two lifelong, complicated friends. While spanning five decades and numerous locations, it is staged simply, with two actors behind desks or sitting in cozy chairs, letting their words describe a world of emotion.