Note: tweets contained in the article feature strong language.
The family got together to get the house ready for Derek's (Ross Boatman) birthday party, with all the tensions you can expect. Oh, and Kelly (Lisa McGrillis) drops the bombshell that she and Jason (Sam Swainsbury) are expecting a baby.
Jason, meanwhile, seems more concerned that his phone drops straight from 50% down to 20%.
Cathy (Lesley Manville) had a personal triumph, as she finally openly admitted that Michael (Peter Mullan) is her partner, and told Pauline (Dorothy Atkinson) to go f**k herself.
#Mum great scene Cathy admitting Michael is her partner 😀- Oli from Reading (@OliReading) June 19, 2019
After a dreadful pep talk from Jason ("you're so confused, you don't even know you're confused"), Cathy decided she didn't want to play hostess with the family and ran off with Michael, some booze and a bag of crisps to go do... who knows what in the bushes.
It was a suitably subtle ending to the show, and while viewers were sad to say goodbye, they thought it was a great send-off.
If you can, pls watch #mum. Genius writing & acting; an ending that is just perfect. My own mum loved this prog & was so looking forward to the final series. Sadly she died in Feb. She could relate to Cathy having lost her soulmate, my dad 7 years ago. Well done @BBCTwo & thank u- Rosie G (@Rosie27) June 19, 2019
#Mum Sweet episode, I did expect something a bit more reactionary but there were several small 'fight back's instead - fitting perhaps with the steady style of the whole show. Can't believe it's the end!!!- Oli from Reading (@OliReading) June 19, 2019
Hurrah for a happy ending! A little piece of perfection. 👏 #mum- Maggie Mossop (@MaggieMossop) June 19, 2019
What a glorious ending to what has been a true joy to watch over the last couple of years. A brilliantly written, brilliantly acted comedy by a fantastic ensemble led beautifully by Lesley Manville and Peter Mullan who have produced on screen gold. #Mum- Tim A Roberts (@Tim_A_Roberts) June 19, 2019
#Mum yay, at long, long last. About time too. Wonderful show, and will miss it.- marie eaton smith (@marie1026) June 19, 2019
Perfect end. Like social media personified, and true to form, everybody's got an opinion #mum- Katherine Ramsey (@KRamsey1997) June 19, 2019
#mum just a work of low key comedy genius. So well acted and written. I'm gonna miss it when it's gone- david oliver (@mancunianmedic) June 19, 2019
Writer Stefan Golaszewski, who also created BBC Three's Him & Her, previously explained why this was the perfect time to end the series.
He told Digital Spy: "The story’s finished. It’s a bit like Him & Her, really [which wrapped after four series]. I set off with an idea of where these characters were going at the start, and the journey that they should go on.
"So once that journey comes to its natural conclusion, the story’s finished. I mean, you could carry it on, I suppose, but you’d be doing it for all the wrong reasons. I didn’t want to flog it for the sake of it, and I don’t think that would be a very kind thing to do the audience, either. If there isn’t a story to tell, don’t tell it."
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