The Emergency Medical Hologram Mark Twelve (EMH Mark XII), also known as Charlotte, is a Holographic program deployed on the USS Antechrist with the intention of providing assistance to Starfleet medical personnel in an emergency or to take command of said medical personnel if the Chief medical officer or Assistant Chief medical officer are unavailable and no one among the present medical personnel is assuming the leadership role in the absence of the Chief medical officer or Assistant Chief medical officer. (Star Trek: False Vacuum)