Family drama about a widowed novelist and his newly adopted son. Science fiction writer, David Gordon (John Cusack) is feeling alone after the death of his wife two years previously. He is weighing up the possibility of adopting a six-year-old orphan boy, Dennis (Bobby Coleman), who believes he is from the planet Mars. David's sister, Liz (Joan Cusack), tries to talk him out of adopting the boy as he doesn't know the first thing about parenting and Dennis appears to be just too far out there. Reluctantly at first, David tries to communicate with Dennis by going along with the child's belief in his Martian heritage and starts to have so much fun being a parent that he stops writing and is about to miss his next book deadline. As the bond between new father and son strengthens, the administrators of the organisation that put them together see David's colluding with the boy's fantasies as a failure of parenting and they threaten to remove Dennis from his care...