Martian Child is a 2007 American comedy-drama film directed by Menno Meyjes and based on David Gerrold's 1994 novelette (not the expanded 2002 novel) of the same name.

The film stars John Cusack as a writer who adopts a strange young boy (Bobby Coleman) who believes himself to be from Mars.

David Gordon, a popular science fiction author, widowed two years prior as they were trying to adopt a child, is finally matched with a young boy, Dennis.

Believing he is from Mars, Dennis protects himself from the sun's harmful rays, wears weights to counter Earth's weak gravity, eats only Lucky Charms, and hangs upside down to facilitate circulation.

Once David decides to adopt Dennis, he spends time getting to know him, patiently coaxing him out of the large cardboard box in which he hides.

While sitting down to write, the flash from Dennis's Polaroid camera catches him off-guard and he accidentally breaks some glass.

David asks Harlee to drive him to the location, where they spot Dennis high up on the outside ledge of the museum's domed roof.

Dennis points out a bright searchlight in a nearby cloud as someone coming to take him home, but David assures him that it's just a helicopter.

While Gerrold had, in real life, adopted a son as an openly gay man, in the film the protagonist is straight and has a female love interest.

[2][3][4] Gerrold has expressed disappointment that the producers forced the protagonist to be changed from a gay man to a straight widower but felt it was a worthwhile trade-off to get published a story about a child in a group home needing a parent.

The site's consensus states: "Despite some charms, overt emotional manipulation and an inconsistent tone prevents Martian Child from being the heartfelt dramedy it aspires to be.