The sector where the Romulan warbird Khazara was to hand three high-ranking defectors to a Corvallen freighter in 2369, and where the Enterprise waited on the word of Stefan DeSeve.
The Kaleb sector appears in the Next Generation episode Face of the Enemy. Subcommander N'Vek, working with Spock's underground, has arranged for Vice-Proconsul M'ret and two aides, hidden in stasis, to be passed to a Corvallen cargo ship there. Deanna Troi, disguised as a Tal Shiar officer, is aboard the Khazara to make sure the transfer happens.
At the rendezvous N'Vek realises the freighter's captain cannot be trusted and destroys the vessel, leaving the plan in ruins and Commander Toreth deeply suspicious.
Meanwhile the returned defector Stefan DeSeve delivers a message from Spock that sends the Enterprise to the same sector. Picard arrives too late, finds the wreckage and begins searching for the cloaked warbird.