Why should parents sacrifice their art by having children when it’s just as easy to incorporate the kids into the act as involuntary performance artists? Jason Bateman stars in and directs this blackish comedy about a suffocating couple (Christoper Walken and Maryann Plunkett), whose guerilla-style exercises in video tomfoolery made them the darlings of the underground art world. Bateman and Nicole Kidman, too old to convincingly pull off this sibling pair, would have fared better as the parents. (The part of sister Annie Fang would have made a great comeback role for Lindsay Lohan.) For too much of its running time, Fang lacks bite, most notably when hints of incest, an apparent familial byproduct, are brushed off almost as soon as they surface. A touch of mystery (are their folks dead or is it another elaborately staged prank?) moves things further uphill until an unforeseen third act reveal cascades into a means-justifying end. (2015) — Scott Marks