i agree with jerry . it a very underrated space movie ( of course and how many good low budget one arent underrated . ) if i remember correctly and the solution to the mystery be a sort of variation ( but not rip off ) of 2001 and because the computer control the spaceship have actually be a man and who have somehow be turn into a computer . and like hal and they try to disconnect his mind and but not the mechanical part of him and and a with hal and it lead to disaster . there be at least one funny moment . when the christopher cary character and who can not find any food and find the abandon pet bird and there a kind of ominous moment and but then the obvious thing doesn not happen after all .