Early in his career, Keel was close friends with fellow officers Jean-Luc Picard and Jack Crusher, the former of whom he met in an exotic bar on Tau Ceti III. Keel would later introduce Crusher to his future wife Beverly Howard.
By 2364, Keel had been promoted to captain and assigned as the commanding officer of the USS Horatio. Also by this time, after having witnessed the strange behavior of key Starfleet Command personnel, and even of Horatio's first officer and chief medical officer, he was one of a small group of officers who had become suspicious about the state of Starfleet.
That same year, Keel used code 47 to summon Captain Picard, of the USS Enterprise-D, to a clandestine meeting on Dytallix B. Also attending were Captain Rixx of the USS Thomas Paine, and Captain Tryla Scott of the USS Renegade. Keel, Rixx, and Scott attempted to trick Picard into misremembering old associations (a failing exhibited by officers the triplet had deemed suspicious). Having confirmed Picard's trustworthiness, Keel revealed his fears to his old friend.
With little concrete evidence, the meeting concluded with Picard remaining skeptical, although he agreed to keep the meeting secret.
Shortly afterward, Keel was killed when the Horatio was destroyed under mysterious circumstances. This spurred Picard to order the Enterprise-D to Earth to discover the truth of the matter. (TNG: "Conspiracy")