ST:TNG:149 - "Rightful Heir" (Stardate: 46852.2) - this is the 23rd episode of the 6th season of Star Trek: The Next Generation.
When Worf makes a religious pilgrimage to the planet Boreth (because he felt spiritually empty ever since he rescued the Klingon children in "Birthright"), where the followers of Kahless the Unforgettable (the first Klingon Emperor who reigned 1500 years ago) wait for the Emperor's return, Kahless suddenly appears to him.
Back on the Enterprise, Gowron (Robert O'Reilly making another TNG appearance) insists Kahless is an imposter.
It's up to Worf and the Enterprise to discover the truth . . . and that truth will have lasting repercussions for the Klingon Empire.
Trivia note: Data continues his night watches on the Enterprise. Riker also notes that Worf is never late to his post (this episode is the first time - he would again be late for his post in Star Trek: Insurrection but for a different reason). Furthermore, we learn that Kahless created the batleth sword 1500 years ago. And, it is noted that there hasn't been a Klingon Emperor in 3 centuries.
When Worf makes a religious pilgrimage to the planet Boreth (because he felt spiritually empty ever since he rescued the Klingon children in "Birthright"), where the followers of Kahless the Unforgettable (the first Klingon Emperor who reigned 1500 years ago) wait for the Emperor's return, Kahless suddenly appears to him.
Back on the Enterprise, Gowron (Robert O'Reilly making another TNG appearance) insists Kahless is an imposter.
It's up to Worf and the Enterprise to discover the truth . . . and that truth will have lasting repercussions for the Klingon Empire.
Trivia note: Data continues his night watches on the Enterprise. Riker also notes that Worf is never late to his post (this episode is the first time - he would again be late for his post in Star Trek: Insurrection but for a different reason). Furthermore, we learn that Kahless created the batleth sword 1500 years ago. And, it is noted that there hasn't been a Klingon Emperor in 3 centuries.