Wendy Richard is to quit her role as Pauline Fowler in EastEnders after 21 years.
The actress will bow out this Christmas in a dramatic storyline.
She said: "When Julia Smith, the very first executive producer of EastEnders, first approached my agent to invite me to play the part of Pauline Fowler I never would have thought that 22 years later I would still be playing her.
"But nothing lasts forever. I've loved every minute of being part of this fantastic show."
Richard was in the first episode in February, 1985. She is one of only two cast members who have been with the soap from the start - the other is Adam Woodyatt, who plays Ian Beale. Her spokesman said she had decided to pursue fresh challenges.
"There have been no arguments or quarrels. Wendy just felt it was time to move on," he said. "She resigned at the end of last year but agreed to stay on for the Christmas storyline. She got to the point where she thought, 'How much further can I go with this role?' Wendy is looking forward to new challenges. There was life before EastEnders and there will be life after."
Long-suffering Pauline's memorable storylines include giving birth to son Martin aged 41, coping with husband Arthur's mental breakdown and death, discovering son Mark was HIV positive, and finding out daughter Michelle was pregnant by Dirty Den.
Before EastEnders, Richard was most famous for playing shopgirl Miss Brahms in hit Seventies sitcom Are You Being Served?
