Screenwriters love genre pieces because they provide definition and structure. When all else fails, scribes can always fall back on their audience's understanding of the way the genre game is played.
Redemption movies and science fiction films are popular genres that have thrived since moviemaking began—guilt and wonderment have never been out of style. Another Earth, a Sundance darling that has gained attention by word of mouth, follows the latest cinematic trend by combining both genres into one mysterious, if uneven, film. The genre mix isn't as pronounced as in Cowboys and Aliens, which screams its high-concept merger in its title. But Another Earth is still a curious blend that can cause dizziness.