Martian Child

David Gordon, a popular science fiction author, was widowed when his wife Mary died as they were trying to adopt a child. Two years later, David is finally matched with a young boy named Dennis. Socially awkward, Dennis believes he is from Mars and only goes outdoors when under the cover of a large box to block out the sun's harmful rays. Although initially hesitant to adopt a boy by himself, David recognizes a part of him in Dennis and slowly coaxes him out of the box and into his home. Read more on Wikipedia.