In 2368 Ensign Ro Laren and Lieutenant Commander Geordi La Forge of the USS Enterprise-D were accidentally cloaked by this device during a rescue mission aboard a Romulan ship that had become disabled while testing the cloak. Mirok was the science officer of the ship and had taken command after the captain had been killed in an explosion.
As he didn't want the Federation to know about the device, he ordered to set up a muon feedback in an energy beam from the Enterprise-D, so that the Muons would accumulate in the dilithium chamber, causing the Enterprise-D to explode when going to warp. Nevertheless, he thanked Captain Jean-Luc Picard for helping his crew when his ship was repaired and flew away, convinced the Enterprise-D would explode soon. Fortunately, this was prevented when Ro and La Forge rematerialized and told Picard of Mirok's plan. (TNG: "The Next Phase")