Kelvin is a man living a stereotyped rational life outside of himself after the loss of his wife. From here he is suddenly called to a distant world to investigate some strange happenings there. After his arrival he almost immeditately becomes exposed to the influences this world have upon people living close to the atmosphere of a planetary organism compososed of psychological life. Awaken by this, the reality of his lost wife comes to life again in her becoming an actual physical presence. And by not believing this to be authentic or real, he sends her out into space the first time she appears to him. Guilt ridden, he goes through his loss of her. Of what she represented in him. But then she appears to him again. This time he discovers that she can heal herself after she tried to commit suicide a second time by drinking liquid oxygen because of Kelvins rational onesidedness. He sent the first image of her out into space alone, even though he knew that being alone was extremely frightening to her. The second appearence found out what he did. And forced him to answer for it. Meantime she communicates with the little boy that has appeared as the son of his good friend and mentor who made him go into space in the first place. It was this boy he first met and recognised when he arrived at the station.
And in the end, that boys relation to the living image of his wife creates a stand off between his colored and rational science officer, a woman physisist, and his wife. And the choice to stay put with the image of his wife created by this world when the station was to become engulfed by the expanding nature of this psychological world, and to live with the symbolic reality of his wife as a man capable of healing himself, or to return to his former life on earth.
He made the choice to stay true to the image created for him by this world through the apparition of his wife.