Mona Lisa (Earth-5875)

The Mona Lisa was a prison ship in service during the First Contact War which carried dangerous convicts to penal colonies.

History
One month after the Battle of Installation 04, the Office of Naval Intelligence had Major John Smith and his science team take over the command of the ship, which they intended to use as a makeshift research laboratory in an attempt to control xenomorphs and use them as bioweapons against the Covenant. They brought sangheili prisoners of war onboard to use as test subjects, and later took the human inmates in the ship. The Mona Lisa jumped to the wreckage of Installation 04, in the Soell system, where they recovered many Ovomorphs to open and impregnate sangheili and human prisoners with Facehuggers. The xenomorphs, however, were easily able to break quarantine and spread through the whole freighter, eventually building a Proto-Keymind in the engine room in an attempt to use the vessel to jump to slipspace and spread to more planets.

Weeks later, the UNSC sent the UNSC Red Horse, a prowler, to investigate the loss of contact with the Mona Lisa. A squad of UNSC Marines aboard the Horse, led by Sergeant Zhao Heng Lopez, were sent by Commander Tobias Foucault to board the ship. There, they separated and were supposed to initiate the Cole Protocol by purging the database of the vessel, but quickly found themselves overwhelmed by xenomorphs. Only two prisoners, a sangheili only known as Henry, and the double-Y syndrome sufferer Patrick Rimmer, were able to survive, alongside Major Smith himself, who locked in the panic room to not get killed.

Design
As a prison ship, the Mona Lisa was a converted freighter used to transport convicts and ore to and from penal colonies. Much like the colonies themselves, the Mona Lisa had no onboard weapons to ensure escaping prisoners would not use them. Large and heavy, the hangar bays of the vessel were located in front of the lower decks and near the prison cells. The bridge was located in the upper decks, near the kitchen, mess hall, and infirmary.