We haven't seen the reality stars on our screens for quite a while but they revealed via Twitter that they've filmed scenes for the last episode of the 19th series.
In a video posted by the TOWIE official website, Frankie says: "Guess what guys! surprise! He's back, I'm back, we're all back!"
Mario adds: "We are here for the beautiful Chloe Sims' birthday. And I was her surprise! Some people would rather have a car and stuff but she got me. Yeah!"
We're sure plenty of people would like you too, Mario!
Frankie, who is Joey Essex's sister, appeared in The Only Way Is Essex from series two until ten, and then popped up again for a couple of cameos in series 14 to support cousin Chloe Sims, who was going through a tough time.
A source told The Sun that Frankie, 29, has also filmed scenes showing her at Chloe's birthday brunch. "It seemed natural for Frankie to be there as they are so close – it was the perfect opportunity for her to dip her toe back into TOWIE life," said the insider.
"Frankie has been working extremely hard to get confident again with her body. Now she's lost weight and got healthier, it's given her a real boost and she feels it's the right time to revisit her old friends and be back on TV."
Recently, she's been making headlines after showing off a new slimline figure following dramatic weight loss. She's gone from a size 16 to size 8 through a new healthy eating and exercise programme, which she'll reveal in an upcoming DVD.
Mario, meanwhile, quit the series in August last year, but made a special appearance during the December Christmas special in a scene which saw him giving Billie Faiers' daughter Nelly her Xmas present.
TOWIE's series finale airs Wednesday at 10pm on ITVBe.
10 reasons why we want to be in TOWIE:
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