'Derry Girls' final season: What time is it on tonight? Who is in the cast?

Derry Girls S3 Specials (L-R) Michelle Mallon (Jamie - Lee O'Donnell), Orla Mccool (Louisa Clare Harland), Erin Quinn (Saoirse Monica Jackson), Clare Devlin (Nicola Coughlan), James Maguire (Dylan Llewellyn)
Derry Girls is back for a final series. (Channel 4)

Derry Girls begins its third and final season tonight as the gang head towards their GCSE results - and the Good Friday Agreement.

The Channel 4 sitcom sets the friendship of a group of teens in the 90s against the backdrop of the Troubles and the series end was always planned to coincide with the peace treaty.

Read more: Nadine Coyle has been planning her Derry Girls character

Here's all you need to know about the last season as the show makes its return for a final time.

What time is Derry Girls season three on TV tonight?

Derry Girls returns for its third and final season tonight (Tuesday) at 9.15pm on Channel 4. The first two seasons are available to watch on All4.

Who is in the cast of Derry Girls season three?

(L-R) Clare Devlin (Nicola Coughlan), Orla Mccool (Louis Clare Harland) Erin Quinn (Saoirse Monica Jackson), Michelle Mallon (Jamie-Lee O'Donnell), James Maguire (Dylan Llewellyn)
All the cast favourites are back. (Channel 4)

Fans of the show will be pleased to know that all their favourite characters are returning to see the show out on its last leg.

Starring as the group of teen friends are Saoirse-Monica Jackson as Erin, Louisa Harland as Orla, Nicola Coughlan as Clare, Jamie-Lee O'Donnell as Michelle, and Dylan Llewellyn as James, or The Wee English Fella.

Read more: Nicola Coughlan calls out interview questions about her weight

Also back is Siobhan McSweeney as nun headteacher and the group's nemesis Sister Michael, Tommy Tiernan as Erin's dad Gerry, Tara Lynne O'Neill as Erin's mum Mary, Ian McElhinney as Granda Joe, and Kathy Kiera Clarke as Aunt Sarah.

Bridgerton star Coughlan, who plays Clare, said: "It was so life changing for all of us. It was a job I got when I was 30. I didn’t know if I was going to ever have a career doing what I love doing, so that’s a privilege on its own.

(L-R) Clare Devlin (Nicola Coughlan), Erin Quinn (Saoirse Monica Jackson)
Nicola Coughlan as Clare and Saoirse-Monica Jackson as Erin. (Channel 4)

"The final season is really a love letter to the fans of the show. That’s why, even after three years, we all fought so hard to get back on set and do this one last time. And I hope we’ve done them proud."

McSweeny, who recently starred in the adaptation of Graham Norton's novel Holding, agreed: "It’s changed my life, this experience, in so many ways. I will never not be Sister Michael. If I’m ever spoken about it will be, 'Oh, she was the nun in Derry Girls.'

"So that has changed my actual bones, my actual identity. I’ve never worked on anything for such a long period of time, and got to work on a character, and revisit a character. That’s so rare in our industry, so that was wonderful."

What will happen in the Derry Girls series finale?

Sister Michael (Siobhan McSweeney)
Siobhan McSweeney as Sister Michael. (Channel 4)

The girls (and The Wee English Fella) are on the eve of their GCSE results as the series opens, and no one has less faith in them than Sister Michael.

But panicking about their academic future isn't the only thing on their minds as they're also still desperately battling to appear cool at house parties and school alike.

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Although few plot details have been released, Coughlan hinted: "There’s a big storyline for Clare this time that I can’t talk about, but (writer) Lisa (McGee) called me a couple of years ago to make sure I was comfortable with it."

(L-R) Sarah Mccool (Kathy Kiera Clarke), Orla Mccool (Louisa Clare Harland), Mary Quinn (Tara Lynne O'Neil), Erin Quinn (Saoirse Monica Jackson), Michelle Mallon (Jamie - Lee O'Donnell)
The girls get their GCSE results. (Channel 4)

We know that the series end coincides with the Good Friday Agreement and McSweeney suggested that there was set to be a sobering finale to the comedy.

She said: "Oh, my God, there should be content warning: This is going to break your heart. Lisa (McGee) has gone full throttle, no tear ducts left standing.

"Our audience will be broken after this. And that’s exactly what they should be, because it’s the final, and it’s a story that deserves to have you broken at the end. Only comedy can break you open that way.

"You’re in for such a treat. Seriously. That finale, you’re going to be broken."

Derry Girls season three begins tonight at 9.15pm on Channel 4.

Watch: Trailer for final season of Derry Girls released on St Patrick's Day