Missandei was originally a slave who served as an interpreter to Kraznys mo Nakloz of Astapor, until she was freed by Daenerys Targaryen. Missandei now serves Daenerys as her trusted advisor and handmaiden. After Daenerys flees Meereen atop Drogon, following an attack from Sons of the Harpy, a Meereenese insurgency organization, Missandei remains in the city as part of her small council. When Daenerys returns to Meereen, with a horde of Dothraki, she achieves peace by ending the war over the Liberation of Slaver's Bay, which is later renamed the Bay of Dragons. Missandei then sails with Daenerys in order to reclaim the Iron Throne from House Lannister, after which she begins a romantic relationship with Grey Worm during their queen's residency at Dragonstone. Following a parley with the Lannisters, Missandei joins Daenerys in response to the northern cause at Winterfell.

Actor must be able to do an Essex English accent. Missandei is very reserved, almost to the point of haughty unsureity. She speaks very deliberately and plainly, which occasionally comes off as obtuse because she was so sheltered from the outside world as a slave. She is a bit naive, but understands broader concepts very well and knows when to play along, and when to keep quiet.