While on a mission to save the planet Lessenar from environmental collapse, the crew of the U.S.S. Enterprise becomes entangled in a web of treachery and murder. When a member of a strange, emotion-casting race is killed on board the ship, all evidence points to Lieutenant Worf and one of his oldest friends. Soon the crew of the Starship Enterprise is crippled by an emotional onslaught as the surviving aliens respond in anger and pain to the death of their comrade. Worf must overcome this alien influence and find the true killer with the destruction of the Starship Enterprise, the survival of Lessenar, and his Klingon honor hanging in the balance.