Director/star Clint Eastwood's "Sudden Impact" is an intriguing addition to the "Dirty Harry" series - a combination of crude film-making and genius. It's mediocre and silly in parts, brilliant and classic in others, with compelling, gripping pacing. There are numerous echoes of the first film here - the shoot 'em up "Make my day" scene recalls the "Do you feel lucky" one, one of the villains is as viscerally repugnant as the first film's Scorpio, an actor who played a minor baddie in the first one returns here as Harry's partner - just to name a few.
Harry Callahan is still at odds with the higher-ups in the department, still mean, still tough, but now he's older and wearier. His constant conflicts with his superiors are a metaphor for his inner conflict - a respect and reverence for the law versus a desire to serve the pure spirit of justice, the two things not always being compatible. This "incompatibility" is the underlying theme of the series. The first film posed a simple question, "What about the victim's rights?" - (do they outweigh those of the criminal? Vice versa? Depends?). That film's answer was controversial, prompting a sequel (the highly enjoyable "Magnum Force") which set out to draw the line between Harry's brand of justice and pure, heartless vigilantism. Dirty Harry, like many of Clint's other roles, is the personification of vengeance, the protector of the the defenseless. This movie however brings it back to the victim, in this case Jennifer (portrayed by Sondra Locke), who decides to avenge the rape of herself and her now-incapacitated sister by ruthlessly hunting down and ritualistically executing the men (and one woman) who committed the crime.
Without going into a play-by-play of the whole movie, I will say this - I mentioned earlier that "Sudden Impact" echoes the first film - it actually also sprinkles in little references and in-jokes from the whole series (the confusion concerning the captain's last name is an example - an intentional prank, I believe). The relationship between Callahan and Jennifer is neat - has our rogue cop hero found a soul-mate in this lady vigilante? And is she a vigilante or a victim justifiably standing up for her and her sister's tarnished rights? The exchange between these two at the very end of the film is a poetic denouement of the series, one which I personally (as a fan) found quite moving. That last scene alone makes Sudden Impact the legitimate climax to the "Dirty Harry" collection, the perfect answer to the conflict posed in the first film. (Not to knock "The Dead Pool" - that excellent movie was a relatively light-hearted suspenseful yet comic thriller featuring Harry Callahan, rather than a character-defining film like this one).
This movie did well in the theaters - audiences in the Reagan Era found Harry and his ilk quite appealing, and the President himself frequently quoted "Go ahead, make my day."

This movie is a muddled mish-mash of clichés from recent cinema. There are some promising ideas in there, but while the director was clearly aiming to wind up with a hauntingly ambiguous film, what he ended up with was a confusing mess. Lead actor Daniel Wu does a fair job but with no central theme it seems as though he doesn't have much to work with. Furthermore, the movie is largely devoid of scares (although, in fairness, there are some creepy moments amid the drudgery).
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We have the mysterious death of an estranged twin, diabolical librarians, ghostly love interests, identity confusion, death by savage monkeys, oedipal conflict, abusive stepfathers, sublimated homosexuality, and crime gang connections. The only real commonality these elements share seems to be that they cause the protagonist to express a vague sense of confusion and discontent.
Perhaps the most disappointing aspect to this film is that despite the brother's death by monkeys being strongly featured on the DVD cover, the act itself is never directly portrayed. Instead, director Julian Lee uses what appears to be stock footage of monkeys - not very scary.
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Avoid this one. For an excellent psychological, ambiguous horror tale, check out the Korean film A Tale of Two Sisters (2003).