Star Trek: Enterprise: Observer Effect

"Observer Effect" is the eleventh episode of season four of the science fiction television series Star Trek: Enterprise and the eighty-seventh episode of the series overall. Combining the totals of episodes from the entire Star Trek franchise, this is the 715th episode. The episode was directed by Mike Vejar with a script written by Judith Reeves-Stevens and Garfield Reeves-Stevens. It first aired on UPN on Friday, January 21st, 2005.