The estimable, controversial 2001 Sundance prize-winner, The Believer, which recently aired on Showtime, finally gets a theatrical release. The explosively talented Ryan Gosling (''Murder by Numbers'') stars as Danny Balint, a laser-bright Orthodox Jewish young man who becomes a neo-Nazi skinhead out of a twisted, erudite, love-hate of his own God. He's Daniel in the lion's den, or maybe Jacob wrestling with the angel, religious passion entwined with self-hate and self-destructive impulses. This intense project, a directing debut for screenwriter Henry Bean (''Internal Affairs''), provokes, troubles, and shocks, perhaps even more in the current world climate than when it was made; sometimes it even crosses into a wilder fervor than a less confident supporting actress like Summer Phoenix, as a Jew hater–turned–Torah student, can convincingly carry. But Bean's commitment to serious theological examination is exciting, Gosling's performance is riveting, and this fiery and imperfect feature shines as a demonstration of independent filmmaking at its most uncompromising.