I saw David O. Russell’s Joy (D+) so you don’t have to. Loosely based on the life of a divorced mom who transforms herself into the entrepreneur of the Miracle Mop empire in the early days of television home shopping, this maudlin seriocomedy takes roughly 90 minutes before it gains a pulse. By the time the story stirs any momentum in a prolonged TV studio sequence, Russell has already failed to generate any consistent tone or believable characters. Bits of the inspirational loosely true story and some facets of Jennifer Lawrence’s occasionally compelling performance as the title heroine (Mother of Invention? Mopping-Jane?) are the only components that bring any life at all to the proceedings. The auteur’s usual repertory ensemble including Robert DeNiro and Bradley Cooper are painfully dull and inconsistent in their roles. The final reel unspools unceremoniously to the finish line but can’t compensate for the inert narrative that led us there. For a film about a magnate of retail, the writer/director fails to make the sale.