all right and i will grant you that some of the science in doppelganger ( or journey to the far side of the sun ) be kind of dopey . the idea of an entire planet exist undetected ( because we can not see it on the other side of our sun ) doesn not hold up at all any astronomy 101 student know that another planet the size of earth would cause gravitational perturbances in the motion of other planet . that how astronomer deduce the existence of pluto and after all and and that how they find comet and asteroid and moon on a regular basis . and the idea that a mirror image earth somehow evolve in almost perfect parallel to our earth and down to english speaking scientist and human counterpart for each human bear on our earth . that take thing out of hard science fiction and into twilight zone territory . that not necessarily a bad thing and but it require a major suspension of critical thinking to accept and enjoy . but man and this movie knock my sock off a an adolescent . i be still use to fairly cheerful and upbeat science fiction film when the hero win through in the end even 2001 could be interpret a have an upbeat end . but in this case represent thinnes attempt to dock with his orbit mothership so he could return to his own earth and only to be bounce back out of his dock berth ( something about the polarity not be reverse because his wouldoppelganger wasn not do the same thing . apparently thinnes wouldoppelganger have decide he be happy in his new home . ) thinnes ship start the descent back to the counterearth launch site and and i be certain that he would somehow get the damage craft to land safely and try again and arm with the new info that would let him and his backer succeed . he be the hero after all and and the hero always win through in the end . instead and thinnes couldn not maintain control of the cripple craft and and the ship subsequent crash into the launch site be so horrible and devastate that it kill everyone ( except for the chief project leader ) and destroy all record of the project and thinnes existence . thinnes never get to go home and and he perish uselessly and his secret never reveal . except for the planet of the ape series and i have never see such a sad and downbeat end and and it always stick in my mind especially the ferocious devastation of the crash scene near the beginning of the move ( you know that spaceship be never go to fly again . ) and the one at the very end . i would love to see this movie again and and see how well it hold up over the year .