The pictures show vigilante serial killer Dexter (Michael C Hall) claiming his first victim of the series, a character played by Dollhouse actor Enver Gjokaj.
Zap2It hints that the crime Gjokaj's character commits will have an unusually personal element for Dexter, and that it will have professional and psychological implications for his co-workers at the Miami Homicide Department.
Executive producer Scott Buck has promised that the premiere will deal with the repercussions from season six's cliffhanger, which saw Deb (Jennifer Carpenter) discovering Dexter committing a murder.
Buck's fellow exec Sara Colleton has described the new episodes as being about "shame and betrayal".
> 'Dexter' season seven poster unveiled by Showtime: 'He saw. She saw.'
> 'Dexter' star Jennifer Carpenter hints at season seven romance twist
The seventh season of Dexter premieres on Showtime on September 30.
Watch Carpenter discussing the show with Digital Spy below: