Starfleet sends the Enterprise on an urgent mission to rendezvous with a special emissary with crucial information, and it turns out the emissary is the half-human, half-Klingon woman K'Ehleyr (Suzie Plakson, appropriately tall and formidable, but also personable), who was involved in some mysterious way with Worf six years earlier. Worf is not pleased to see her.
I gotta say: I wanted to like this episode — with its Worf character development, Klingon angst that turns to Klingon sex, and, of course, Suzie Plakson — but ultimately it just doesn't work. K'Ehleyr briefs the Enterprise staff on the situation: A Klingon ship whose crew has been in stasis for the past century (and thus still thinks the Klingons are at war with the Federation) is about to awaken, and the Enterprise may be the only ship close enough to stop them before they unleash a fury of terror on nearby Federation colonies. I find this plot just a little bit ludicrous. The Klingons of the old era are seen as not merely aggressive, but also apparently as mindless drones — and besides, where would the honor be in destroying colonies with minimal defenses?
More interesting is the backstory that surrounds Worf and K'Ehleyr; they had an unconsummated relationship six years ago, and they haven't spoken since the relationship ended. This episode establishes Worf's attitude on relationships, which is that they must be taken seriously — as seriously as, say, a heart attack. K'Ehleyr, unlike Worf, has an outward sense of humor, but pursuant to all Trekkian characters who are trapped between cultures, she struggles with her Klingon temper. Unfortunately, the Worf/K'Ehleyr bickering is not performed well enough to transcend cliche.
The high point of the episode comes when K'Ehleyr uses Worf's holodeck exercise program and Worf joins her in a battle that turns to (apparent) heated sex. I guess one of my problems with the episode is that the sex and its aftereffects are kept so far off the screen that it's something of a letdown. The episode tiptoes around the word "sex" so carefully that it doesn't seem like the characters actually had it. Worf's attitudes on sex are the same as everything else — he takes it as a deadly serious enterprise that must end in marriage (which K'Ehleyr doesn't want) and doesn't seem to know what fun is. You've got to admire his personal code.
Worf also gets his "first command" in a scene of trickery that persuades the Klingon ship to stand down. Unfortunately, like a lot of the episode, the concept is better than the execution, which feels forced.