To Kill a Mockingbird.Harper Lee's To Kill a Mockingbird is an institution, a must for every high school curriculum, the inspiration for a well-loved film starring Gregory Peck and scripted by Horton Foote, the starting point for discussions of race ever since the novel first appeared in 1960. Unfortunately, Christopher Sergel's stage adaptation, like so many novel-to-play enterprises, is a plodding, static affair. While the book's characters are brought to life by Lee's vivid, poetic description, the characters onstage are flat — and it's hard to believe that anyone, anywhere, ever really spoke as they do. The story is narrated by an adult version of Finch's adoring daughter, Scout. As six-year-old Scout and her brother, Jem, play with an eccentric visiting boy called Dill, speculate on a reclusive neighbor, and struggle to fathom their father's work and the mysteries of the grown-up world, the narrator hovers benignly. It's charming at first, less so as the evening progresses. The second act, in which Finch defends Tom Robinson, the alleged rapist, is more involving, though the characters remain unconvincing. Finch is consistently noble, dispassionate and courteous; Tom humble, polite and subdued. If the man is terrified — he's barely escaped a lynching, after all — he doesn't show it. Like Tom, most of the black characters are primarily window dressing. The Finches' maid, Calpurnia, is strict but loving. During the trial, a group of black townspeople sit in the balcony like a Greek chorus — except they don't even get to comment. Insightful direction could perhaps rescue the play, but Sabin Epstein's production is as straightforward and unimaginative as a preachy after-school special. Presented by the Denver Center Theatre Company through October 30, Stage Theatre, Denver Performing Arts Complex, 303-893-4100, www.denvercenter.org. Reviewed October 13.