...und immer ruft das Herz

Dr. Peter Holmes (Carl Moehner), zoologist and veterinarian, relectantly agrees to permit his dog, Wolf, to be used in a launch project commissioned by the International Conference of Science, at Geneva, to study body function and survival in outer space. Holmes had discovered Wolf as a pup in the forest, only to lose him again in a flood, and is fearful of risking the dog's life again.