But the show's writers have got a lot of explaining to do to bring him back, because he's supposed to be dead!
In his final scene Den, who was in trouble with local gangsters, appeared to have been shot and killed.
Even though Den hasn't been on the show for years, there are three of his kids in the square:
The actor who plays Dirty Den - Leslie Grantham - will start working on the show next month, although he won't be on screen until September.
His most famous moment was on the Christmas Day episode a year later, when 30m fans watched him give wife Angie divorce papers as a present.