Waitress takes on added poignancy when you know the story behind it. Actress Adrienne Shelly, a staple of the New York indie film scene since the late 1980s, was poised for a breakthrough as a director with this romantic dramedy. After the film was completed but before its Sundance premiere, Shelly was murdered in a Greenwich Village apartment. Waitress is an appropriate valedictory, a gently feminist celebration of love, life and motherhood. Keri Russell (best known as TV’s “Felicity”) stars as a great waitress and pie-maker stuck in a bad marriage (to a scruffy, clueless Jeremy Sisto). She falls for her gynecologist (Nathan Fillion) and struggles toward independence. Russell carries the film pretty well, and the deadpan Fillion is an odd but endearing choice as her romantic foil. The men in the film are completely out of focus, anyway, except for Andy Griffith (!), who appears in several scenes playing a creaky old plot device. The biggest problem is that you’ve seen this story many times before: woman in bad marriage (but with spunky friends) thinks she can’t get out from under, but eventually finds the courage to make a new start. Still, as summer movies for grownups go, it’s not bad at all.