The Empty Crown was a faction within the Romulan Star Empire that believed that the Romulan people had grown too weak to combat enemies like the Federation and needed better, more stronger leadership.
In 2380 a race of bio-engineered creatures known as Exomorphs appeared. Commander Suldok, a high-ranking member of the crown learned the location of the Master Control Facility where these creatures could be used to suit his needs. Suldok attempted to take over the facility but his plan was foiled by Alexander Munro. (Star Trek: Elite Force II)