The UNSC Midsummer Night is a Paris-class heavy frigate of the UNSC Navy. The vessel was also equipped with a cloaking device which was designed for use against insurrectionists. The device was most likely authorized for use on board the vessel by the Office of Naval Intelligence. Its known captains follow:
CDR Lucas Graduer
The Midsummer Night found the Halo ring after chasing a Covenant corvette. They jumped right into a slaughterhouse, with two corvettes at once. The ship launched her escape pods and mobile bases at once and was then hidden on the ring.
Eventually the ship was found by Perseus, who informed the Spartans and they sent Brass and Whisper aboard. Nightflash planned to escape, but learning Halo's purpose, ordered Brass to reboot the weapon systems. However, the ship was boarded and then destroyed by the corvette.