Carmen (The Raincloud Man)
Carmen was a time traveller and a gambler. She lost her memories in a bet at the high stakes table at Brooks' casino boat. The Sixth Doctor thought that she was abusing time travel to defraud some casinos, and confronted her about it, but could not prove anything. Charley pretended to know her from before she lost her memories to get aboard Brooks' boat. Carmen helped Charley and the Doctor deal with the Tabbalac when they assaulted the ship in Rio de Janeiro. At the end of the adventure she decided she did not need to regain her memories and to stay in Rio, though the Doctor estimated she was originally from the 108th or 109th century based on her time machine. (AUDIO: The Raincloud Man)