The funny and heartbreaking Off the Map, directed with a poet’s eye and a keen ear for nuance by Campbell Scott, resonates with something rare in today’s movies: simplicity. It respects the New Mexico desert setting where Charley (Sam Elliott), his wife, Arlene (Joan Allen), and their eleven-year-old daughter, Bo (Valentina de Angelis, a genuine find), have decided to make their home away from modern conveniences like electricity and running water. And the deft script, which Joan Ackermann adapted from her play, never exploits Charley’s untreated depression, Arlene’s earth-mother tendency to garden in the nude or Bo’s frustration about a life without friends. The entrance of an IRS man (the excellent Jim True-Frost) into this fragile Garden of Eden allows Scott to observe changes, subtle and seismic, in this maverick family. Allen and Elliott perform acting miracles in a quietly devastating spellbinder that sneaks up and knocks you flat.