“Rightful Heir” is episode twenty-three of season six of Star Trek: The Next Generation.
A new shift and Commander Riker take over the bridge from Data in a rare display of sensible officer use. Data fills Riker in and then Riker asks if Worf is supposed to be on duty. He is and he doesn’t respond. Worf is in his quarters so Riker heads there with a security team and overrides the lock. Worf is either performing a ritual or attempting to set fire to his quarters.
Worf is in his quarters when the captain arrives. Picard says that personal affairs are Worf’s own concern until they interfere with ship operations, and that line has been crossed. The captain wants to know what is going on. Worf says it’s difficult to explain. The captain tells him to try.
Ever since Worf returned from the Carraya system in “Birthright, Part II”, Worf has felt empty. He tried to teach the young Klingons their stories, customs and beliefs, including the promise that Kahless would return to lead them one day again. Worf was trying to get Kahless to appear in a vision, and the holodeck wouldn’t have been appropriate. It needed to be real. But nothing happened. Worf is questioning his beliefs but it shouldn’t interfere with his duties. The captain tells him it’s inexcusable. And understandable. Perhaps what he’s looking for cannot be found on the Enterprise. Worf should immerse himself in Klingon beliefs. Is there somewhere he can go? Yes, Boreth, where Kahless’s followers await his return. The captain says Boreth is only 12 days away in a shuttle. Worf is on leave for now but when he comes back, he will need to perform his duties like a Starfleet officer.
On Boreth, a young Klingon has a vision. Worf does not. Worf decides he has to leave after 10 days and nothing. Koroth, the High Priest, says they’ve been waiting on Boreth for 15 centuries, ever since Kahless pointed at a point of light in the sky and said he would return there. What are 10 days compared to that? Worf stays and has a vision of Kahless. The young Klingon runs off. For Kahless is not a vision. He is real. The others come and Kahless says he has returned. He asks if they know the story of how his sword was forged. It’s said that no-one does. Kahless recounts it. And it seems that the priests do know, but never wrote it down, so that if Kahless returned, they could be sure it was him. Kahless says his people fight amongst themselves in petty wars that corrupt the glory of the Klingon spirit. It’s not too late, though. He has returned and will lead his people again.
Kahless finds Worf in his quarters with his tricorder. Worf explains what it is, a tool to see if Kahless is real. Kahless tells Worf to proceed. Worf confirms that Kahless is a Klingon. He might have been a shapeshifter or a hologram. Kahless tells Worf they’ve met before, in a vision in some caves when Worf was a child. He told Worf he would do something no Klingon had ever done before.
Kahless is later told about Gowron. He isn’t worried. He says Klingons from all over the Empire will flock to his banner. Kahless sees Worf still has doubts. They end up fighting, and Worf looks to be doing well, until Kahless starts laughing. He says the Klingons now only fight for anger and bloodlust, not for the joy of fighting and enriching the spirit.
The Enterprise is called in to for try and determine the truth of the matter. Gowron is informed about Kahless’s return. He is not happy and believes Kahless is a fraud. Worf desperately wants to believe Kahless is real. Whether or not Kahless is real, he could easily split the Empire, because no matter what, some will follow his banner. Gowron is rightfully concerned about civil war.