Talitha Bateman plays Heidi, a sheltered preteen who goes on a journey to learn more about her background in this somber tale. (Bonnie Osborne/Outside The Box Prods/Branded Pictures Ent)

Don’t let the cutesy title fool you. “So B. It” might be based on a popular 2004 children’s novel, but director Stephen Gyllenhaal (father of actors Jake and Maggie) and writer Garry Williams have taken this tale of a 12-year-old girl who goes on a journey of self-discovery and fashioned a moody family melodrama that seems mostly aimed at adult tastes. Talitha Bateman plays Heidi, a bright yet sheltered girl who lives with her childlike, mentally challenged mother (Jessica Collins) and agoraphobic guardian (Alfre Woodard, her character doing what she can between panic attacks) in a modest Reno apartment. While she looks the part, the young actress never quite settles comfortably into her role.

Bateman’s best moments arrive early, in a couple of flash-forwards that reveal Heidi showing off her so-called luck in a sheriff’s office as he flips a coin and she correctly guesses heads or tails, 10 times in a row. Bateman herself is lucky to play off Cloris Leachman — still a stitch at 91 — as well as a clutch of kittens, as the girl travels by bus to Liberty, N.Y., in search of answers about her past. But there’s something rather artificial about this somber fairy tale, including the way that Woodard’s Bernie dolls Heidi up in makeup, heels and grown-up garb whenever she sends her underage ward out as her surrogate to the outside world. To the detriment of their story, the filmmakers seem to have forgotten that even the most serious of kid-friendly films can benefit from an injection of fun while attempting to jerk tears.

PG-13. At the Angelika Pop-Up at Union Market. Contains mature thematic elements. 98 minutes.