Season 4 - Star Trek: Deep Space Nine

Season 4 of Deep Space Nine marks a major shift for the series, as it introduces a new conflict between the Federation and the Klingon Empire, sparked by the latter's distrust of the shape-shifting Founders. Worf, the former security chief of the USS Enterprise-D, joins the station's crew as Sisko's strategic operations officer, and faces challenges in his loyalty, honor, and family.