If you took the fighting out of The Fighter, David O. Russell's previous movie, you'd be left with a close, fractious family like the Solatanos of his hugely appealing new Silver Linings Playbook (based on Matthew Quick's novel). Instead of Boston Irish and boxing, we have Philadelphia Italian and the Eagles. The family patriarch (a fine, restrained Robert De Niro) is an OCD bookie bound by strange rituals to the team; his wide-eyed wife (Australian actress Jacki Weaver of Animal Kingdom) is the nervous family conciliator/enabler; and their volatile son Pat (Bradley Cooper, wired) is fresh out of the nuthouse with a restraining order from his ex. Pat's most recent violent outburst has the cops and neighbors suspicious, but he claims he's a new—and newly positive—man. He's looking for those silver linings through self-improvement: reading, running, losing weight, scheming to win back his wife (this last in complete disregard of family and medical advice). His obsession frightens his parents and frightens us—is another explosion near? Russell keeps the film constantly off-balance, with a worryingly erratic tone that sprints from comedy to chaos and back within most every scene. But his pell-mell approach suits the story of Pat's mania and wrong-footed romance with young widow Tiffany. In that role, Jennifer Lawrence is a revelation: tough, proud, and even more titanic in her instability than Pat. But the difference is this: She knows she's unstable, while Pat clings to his optimistic routine. Her darkness complements his sunny denial. Russell builds their uncertain courtship toward a Christmas conclusion, daring us to imagine the worst during this holiday-movie season, yet reassuring us it won't happen. Silver Linings is one of the year's best films, and Lawrence a lock for an Oscar nomination.