A powerful and treacherous Klingon noble house whose leaders betrayed the Empire to the Romulans and twice sought to seize control of the High Council.
The House of Duras was one of the most influential families in the Klingon Empire during the late 24th century. Its patriarch Ja'rod secretly helped the Romulans carry out the Khitomer massacre, and his son Duras later concealed that betrayal by having the blame placed on Mogh, Worf's father, which led Worf to accept discommendation in 2366.
In 2367 Duras challenged Gowron for leadership of the High Council. When K'Ehleyr uncovered the truth about Khitomer, Duras murdered her, and Worf killed him in retribution. His sisters Lursa and B'Etor then backed Duras' illegitimate son Toral as a claimant, plunging the Empire into civil war with covert Romulan support.
The Duras faction lost the war when the Federation blockade exposed the Romulan involvement. Lursa and B'Etor remained active as arms dealers and schemers, appearing on Deep Space Nine, until they were killed in 2371 during their attack on the Enterprise-D at Veridian III.