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There is something classical about this story. A big game hunter signs on to a hunt that takes him through time to the Jurassic. The rules here are a little confused. So there is a bit of willing suspension of disbelief. The hunter is warned to under no circumstances leave a well demarcated trail as he hunts for a dinosaur. Lest he disturb the slightest thing in that time frame. The implication being that the ramifications of the tiniest perturbations magnified over millions of years can seriously change the future. Somehow the effect of the killing of a dinosaur in my memory is either ignored or explained away inadequately. Predictably the hunter steps or slips off trail crushing an insect. When he returns to his present every thing is just a little off and he cannot regain the perspective of being home.