Though Christmas is not a time of cheer for all, for many it can at least be a time of hope. And while Conor McPherson's one-act play posits that hope is possible for its emotionally damaged fiftyish undertaker John, the playwright makes his audience work for the right to believe in John's redemption. While Dublin Carol is inspired by Dickens's A Christmas Carol and the author shamelessly names its characters John, Mark, Mary and (the offstage) Noel, there is nothing else easy or sentimental about this uncompromising play.