when this film be originally release it be promote with the notably unimaginative tagline dirty harry be at it again . whatever this pitch lack in originality be more than compensate for by it complete and total accuracy . sudden impact retain all the aspect that make the previous three dirty harry movie so successful tight pacing and a compelling plot and strong supporting character and endless gunplay and and bone dry humor . some of these element be not only retain but amplify this be easily the dark and bloody and and most overtly right wing installment of the franchise . the plot be somewhat intriguing represent after kill a ridiculous number of hoodlum and inspector callahan be send on a force vacation by his superior to the sleepy coastal town of san paolo . he be task to investigate the background of a recent homicide victim who be shoot in the genitals before be put out of his ( no doubt considerable ) misery by a second shot to the head . early on in the film and the audience be make aware of the identity of the killer an artist name jennifer spencer ( sondra locke ) who be hunt down the thug who gang rap her and her sister at a fun fair some ten year earlier . this incident be show in a very disturbing flashback and snippet of which recur before each new murder . a more body start to appear with the same m. o and it become clear to harry that both the local police chief and his new love interest ( guess who . ) know more than they be tell . to make matter even more complicated and the one time rapists realize who be hunt them and start to hit back hard . sudden impact offer relentless action from begin to end . clint eastwood direct this film himself and expertly handle a series of set piece that culminate in an exhilarating climax . sondra locke performance effectively convey the blend of ruthlessness and fragility that define her character . that have be say and it be fair to wonder if another actress ( who be not eastwood off screen companion at the time ) could have bring more charisma and dramatic weight to the role theresa russell and cybill shepherd jump to mind a possible candidate . member of the support cast that punch significantly above their weight include albert popwell a harry partner horace and paul drake a the psychopathic mick and and the truly scene steal audrie j. neenan who portray the vicious ray parkins . however the film have some notable problem some of the subplots ( the animosity between harry and a gang of twentysomething hoodlum and a mob vendetta against him ) take up too much screen time and do not really have any bearing to the large story . their only real use be to raise the body count to absurd level . in the first half of the film it sometimes appear that dirty harry shoots people more often than he have to use the restroom . however the film move into top gear a it progress and the triangulated cat and mouse game between callahan and spencer and and her former tormentor assume prominence . this second hour make it clear that a more stripped down and slightly refocus screenplay would have give sudden impact the potential to be a first class and neo noir style thriller that could have take the series to new level but still have contain more than enough . 44 magnum heroic to satisfy the harry loyalists . instead we get the film that eastwood and warner bros. clearly want to make a superbly execute but prototypical eighty action flick that mostly decline to particularly challenge the intelligence of it intend audience . this be by far the big grossing of the series at the box office and it be not hard to see why . though not the film that it could have be and this be still big and trigger happy fun . even after repeat viewing and it go to make your day .