The 45-minute special, The Agreement will air on Channel 4 in the same week as series three comes to an end and is set one year later.
Dealing with a key moment in Northern Irish history, the Good Friday Agreement vote, the extended episode running over 45-minutes will air the same week as the third and final series comes to a close on Channel 4.
For this special instalment, we return to Derry one year later as the gang prepare for their final year of school. It’s the week of the referendum on the Good Friday Agreement and its timing couldn’t be any worse as the highlight of the year, Erin and Orla’s joint 18th Birthday party, threatens to be overshadowed.
While the family try to get their heads around the possible outcomes of the vote, the gang realise that they may not be ready for what the future holds.
Speaking about this special final treat for fans, writer and creator Lisa McGee said "Like all the very best 90s bands, I couldn’t resist ending our farewell tour with an encore for our loyal fans. I'm delighted to say we'll be returning for one extended special - airing in the same week as our final episode."
"The special deals with the historic and momentous Good Friday Agreement vote, which coincides with the gang’s coming of age, they enter adulthood just as Northern Ireland embarks on a new future. I’m so proud of this show and of our incredible cast and crew and everything we’ve achieved over the past 5 years."
"What a journey it’s been. I'm so grateful Channel 4 gave me the space to end the stories of these characters that mean so much to me with this special. I really hope the fans love it as much as I do . Derry people aren’t great at saying Goodbye so I will instead use one of our native expressions “ That’s us away now”, Love Lisa McGee, always a Derry Girl."
Derry Girls continues Tuesdays at 9pm on Channel 4