Derry Girls has become a global phenomenon since it came onto our screens in 2018.
Since then, it has made us laugh, cry and laugh again with the combination of top-notch writing from creator Lisa McGee and hilarious performances from the cast.
It is no surprise that a number of famous faces have popped up across the Channel 4 hit's run, with many guest stars admitting they are big fans of the show.
Read more: Review: Derry Girls series 3 starts the beginning of the end
Here are some of the big names to appear on the show so far:
Liam Neeson
The whole country was in collective shock when in the first episode of the third series out of the darkness in the 'Londonderry RUC station' appeared Hollywood A-lister Liam Neeson.
Tasked to question the girls (and James) who were caught breaking into the school he was eventually worn down by Uncle Colm's never-ending drone as the gang tactically call him in as their 'responsible adult'.
Speaking at a Q&A after the premiere of series three, Lisa McGee said they had been using nicknames to disguise the indentity of their mystery guest star to ensure that it would be a major surprise for the audience.
Ardal O'Hanlon
Played Eamon, Mary and Sarah's cousin, Irish actor Ardal O'Hanlon made a lasting impact on fans when he appeared in the second series.
Son of Aunt Birdie who died at a family wedding after Ma Mary’s “curse”, Eamon was the definition of a mummy's boy who couldn't even get a place in rock the boat.
The actor is most known for his portrayal of Father Dougal in the hit comedy series Father Ted - which creator Lisa McGee has said on many occasions that she is a big fan of.
Packy Lee
Belfast actor Packy Lee made a short but sweet appearance in this week's episode.
Most well known for his role as Johnny Dogs on Peaky Blinders, Packy played 'The Stranger on the Train' in the third instalment of the third series that aired on Tuesday.
In a case of mistaken identity, the poor stranger on the train gets accused of not only being a terrorist but for stealing a precious packet of Tayto Salt and Vinegar - when in reality, he is just a kind man looking after someone's bag.
Kerri Quinn
Playing the wild van-driving "maniac" in the episode titled 'The Concert', Kerri Quinn's character Rita lets the gang hitch a lift on their way to the Take That show in series 2.
From Belfast, Kerri can be recognised for playing Vicky Jefferies in Coronation Street, Sgt. Marlene Pettigrew in NI crime drama Hope Street and her appearance in Three Families.
Amy Huberman
Irish actor Amy Huberman joins the list after her cameo appearance on Episode 3 of the hit Channel 4 comedy's final series.
As Clare gets stranded at the train station with Sister Michael, Amy plays a station worker who gets a little too loud about her personal life while on the job.
Chatting on the phone in her ticket booth, Amy's character gets into the painful details of her romantic instability - not the kind of details you should be sharing in front of a teenager and a nun.
Sinead Keenan
Describing featuring on Derry Girls as "something to tick off the bucket list", Irish actor Sinead Keenan joined Packy Lee and Amy Huberman on that dreaded train to Portrush in episode 3.
She is best known to Irish viewers for playing Farrah Phelan in the soap Fair City and is best known to UK viewers for playing the role of werewolf Nina Pickering on BBC Three's supernatural drama Being Human.
She also played Patrica in the Northern Irish comedy-drama My Left Nut.
Who is rumoured to appear...
Although nothing has been confirmed, it is highly speculated that iconic DJ Norman Cook aka Fatboy Slim could be coming to our screens in the final series.
A 'TV insider' told Sunday Life: "Norman has agreed to do some filming for Derry Girls, he's a big fan of the show.
"The show is based in the 90s so it will hark back to when he broke through as Fatboy Slim with big hits like Praise You."
In March, Lisa McGee posted a photo of the DJ to her Instagram page wearing a crew coat that read 'Derry Girls Series 3' which sent fans wild.
Read more: Liam Neeson makes Derry Girls surprise appearance in new series
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