What a year for Park Chan-wook: discovered at Cannes, heralded as a Sophoclean Tarantino, then dismissed or debunked as a pulp poseur just as quickly as he had been embraced. Three films have been released during this span — Oldboy, precursor Sympathy for Mr. Vengeance, and now Sympathy for Lady Vengeance: the fact is, if you liked the first two and took them for what they were (which many refused to do) you can’t defend the director using his latest. A weak retread of his usual themes of retribution and atonement, the last installment of his “Revenge Trilogy” is a classic case of diminishing returns. Lee Yeong-ae stars as the title character, getting even with the demented teacher who set her up; Park’s visual and narrative pyrotechnics work temporarily but can’t redeem one of the most egregious pseudo-snuff sequences ever filmed. Park goes to the well once too often and ultimately comes up empty.