Inside No. 9 finale Plodding On is a cameo fest that Marvel could learn from

By far the biggest and starriest ensemble that the show has ever seen, creators Reece Shearsmith and Steve Pemberton used their swan song Plodding On as a reunion special, bringing together an array of talent from across the past nine seasons.

Fittingly, the roll call kicks off with an entrance from Katherine Parkinson that echoes the show's first ever scene, complete with a discovery of Tim Key awkwardly standing in a confined space.

This time, instead of a wardrobe, it's a toilet cubicle; and instead of a game of sardines, they plan to snort some cocaine to make the Inside No. 9 farewell party somewhat more bearable.

Parkinson hails Shearsmith and Pemberton for the rare achievement of getting their show to nine seasons, but back-handedly adds that it was time to call it quits – after all, it had got a bit "self-indulgent" recently.

It's an understandable lampshade to hang given the premise of this episode, but actually, the writing duo have managed to pen a meta story filled with cameos and fan service that is nowhere near as obnoxious as that description would suggest.

Sure, there are moments in Plodding On that can be seen as the creators blowing their own trumpet – arguably, they've earned the right to – but the focus remains primarily on a compelling narrative about friendship and moving on.

Shearsmith and Pemberton play themselves as they consider what their next move will be after Inside No. 9, with the former keen to stick together for a BBC detective drama, and the latter eyeing a solo move to Hollywood for an epic Prime Video original.

Rather than being superfluous to this plot, the cameos are the device through which it is explored and pushed forward, with Rosie Cavaliero's supposedly secret chat and Nick Mohammed's inept podcast interview being the most enlightening interactions.

While more overtly comical – to the point of literally mooning the audience – even Robin Askwith's scene acknowledges the central theme in a meaningful way, and sets up a killer closing gag expanding on the now mythical bus episode.

Admittedly, that particular reference probably won't hit as hard among those unfamiliar with the context (which includes years of fan demands and a memorable season 8 hoax), but it's seeded well enough so not to completely bemuse a novice viewer.

In an age where such callbacks, cameos and Easter eggs have become an ever more brittle backbone on which so much genre entertainment relies, it's refreshing to see an instance where they have been used effectively in service to something greater.

Marvel Studios, take note.

While it might seem strange to compare the blockbuster superhero franchise with the comparatively modest Inside No. 9, it will be looking to pull a similar stunt to this finale when it wraps up a messy phase with 2027's Avengers: Secret Wars.

Deadline recently reported that the film could have as many as 60 characters, only slightly outpacing Plodding On's 49 credited guest stars (although to be fair, only 11 have speaking roles).

It's a worrying development for a franchise which has increasingly pitched the cameo(s) as its main attraction, with perhaps the most egregious example being last year's The Marvels.

That particular project squandered a talented cast on an ill-conceived script and proceeded to pitch most of its marketing around a violently shoe-horned X-Men connection that comprises roughly 20 seconds of the film.

Producer Kevin Feige could find a more inspired approach from Plodding On, which identifies a sturdy premise with an interesting conflict – two things The Marvels lacked – before carefully implanting a selection of quality cameos.

It sounds like an obvious strategy, but it's one that Marvel and various other pop culture brands have been missing recently.

Inside No. 9's grand finale proves that there's nothing inherently wrong with cameos, but the thoughtful execution of those appearances is vital – and it's something that the MCU once managed relatively well.

Having previously taken cues from the likes of Community, Game of Thrones and Rick & Morty, perhaps it's not impossible that Feige will look next to a little British anthology that has been quietly delivering for the past decade.

If not, at least Inside No. 9 fans can be proud that the series ended on a high note, which just so happened to involve Anne Reid getting high using a note. Bravo!

Inside No. 9 seasons 1-9 are available to stream on BBC iPlayer. You can buy tickets to Inside No.9's West End show Stage/Fright right now.

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