Doctor Who is to welcome the Time Lord's first openly gay companion.
Bill Potts is the latest sidekick to join the Doctor and will reveal her sexuality in her second line of dialogue when the BBC show returns next month.
Pearl Mackie, who plays Potts, told BBC News it was "about time", adding: "That representation is important, especially on a mainstream show."
LGBT characters have featured in the popular series before, including John Barrowman's Captain Jack and River Song, but Bill will become the first openly gay permanent companion.
Mackie, 29, said she found it important for diverse characters to be represented and drew on her personal experiences of growing up and watching television.
"I remember watching TV as a young mixed race girl not seeing many people who looked like me, so I think being able to visually recognise yourself on screen is important.
"(Being gay) is not the main thing that defines her character - it's something that's part of her and something that she's very happy and very comfortable with," she said.
Mackie was announced in the role last April but has had to wait almost a year before appearing on screen alongside Peter Capaldi's Doctor.
The new series of Doctor Who, which will be Capaldi's last in the lead role, begins on BBC One on April 15.
Among those tipped to replace the The Thick Of It star by bookies' Coral are Fleabag's Phoebe Waller-Bridge (10-11), Death In Paradise actor Kris Marshall (7-2) and Oscar winner Tilda Swinton (5-1).