Over at Twenty Twelve (BBC2), the bad days are piling up. In the series finale we are counting down to handover day. With 18 days to go, there seems no solution to the problem of the opening ceremony fireworks setting off the MoD's ground-to-air missiles; the national bell-ringing celebration has received two entries and been repurposed by Siobhan as a competition with celebrity judge Sting, if she can just call in a favour from Davina McCall's pilates instructor Samphire; no one on the Deliverance team has made the shortlist for the Director of Posterity job; and Ian is still having "to think on his feet until he finds out where they've taken him".

It is a good job this was the last episode (even if it did leave the Sally/Ian, will they/won't they question cruelly, cruelly unresolved). As real-life events began increasingly to mimic their supposedly fictional counterparts (both have had security botches, desperate measures to mitigate bad ticket sales and coachloads of people getting lost through driver incompetence and there is every chance that McCall's pilates instructor is indeed fielding innumerable calls from everyone from Seb Coe down) it seemed increasingly likely that the opening ceremony in London would begin and end with the two merging streams creating an event horizon and swallowing the entire thing, Boris Johnson, Siobhan and every other implausible creation in between. Ah, well. Maybe next time.

Twenty Twelve, BBC Two, review

This was a typically subtle finale to what's been a perfectly played and painfully close-to-home satire. It's been funny because it's true.

Twenty Twelve: the finale, BBC Two

This was an exceptionally bold TV idea, to keep apace with current events and constantly spin them into über-comedy. No one could have foreseen how tough the last three episodes would turn out to be, but the programme always had a secret weapon: its G&S-like appreciation of language.

With a certain sporting event looming, it's the last ever episode of this marvellous mockumentary. As the Olympic Deliverance Team prepare to hand over to the Live Team, last-minute panics still need resolving. The fireworks planned by Danny Boyle for the opening ceremony will trigger the Army's ground-to-air missiles. Charging stations for the official Olympic electric cars work so slowly, the entire fleet will soon be stationary. And the special "Big Bong" peal of church bells, supposed to ring nationwide, has so far attracted only two entries. Cue BlackBerry-addicted "branding guru" Siobhan (Jessica Hynes) salvaging the crisis by roping in a celebrity. Will she land Sting or settle for Aled Jones?

Just to add tension, three colleagues have applied for the same post-Games job, with the shortlist about to be announced. Come handover day, Lord Coe isn't around to make his planned speech, having been "called away to argue with animal rights groups about a sheep", so Ian (Hugh Bonneville) steps in. Can he make it a rousing send-off? And will his excruciating but rather moving romantic tension with PA Sally (Olivia Colman) be resolved? Smart, superbly played and painfully close-to-the-bone.

Granted, the recent debacle over employing security guards trumps fiction, but it's still sad to bid farewell to Twenty Twelve. That's principally because it's a comedy that brilliantly skewers both group-think idiocy and the personal rivalries inherent to all organisations. In the final episode, there are 10 days left until the Live Team takes over from the Deliverance crew, time enough for a difficult meeting with Danny Boyle's bruising fixer, Kevin Thingie, a competition to compose an Olympian peal of church bells and for the ever-elusive Seb Coe to be "called away to a last-minute argument".

Ian Fletcher writes about the day of deliverance

Few people have made a greater mark on the public imagination in the build-up to the Games than Ian Fletcher, the can-do, two-wheeled driving force of Twenty Twelve.

In Twenty Twelve, Owen (Olivia Colman) hasn't actually declared her love for her Games-organising boss, but at least she's back as his PA to slice through "legacy", "diversity", "inclusivity" and all that rot, just as she would the lemon drizzle cake with which she keeps him sweet.

Twenty Twelve - The final three episodes of which are on iPlayer - seems to be a strange source of pride for some people, who argue that very few countries would allow their public service broadcasters to paint their officials in such unflattering light on the eve of the Olympics. Sadly, the fun, and the series, ends this week, as the team hand over control to a hopefully more capable bunch.

The first episode of the current seasonette of the wonderful Twenty Twelve (BBC Two) was called Catastrophisation and hit the screen just before the story came out about the Olympics security force being short of several thousand people. The people who make the show must be aware that reality is always going to beat them, but still they plug away, creating, with the Head of Deliverance and his team, the funniest ensemble since Dad's Army. Hugh Bonneville plays Ian Fletcher with a dead pan, yet his eyes are full of the awareness that the only sane course is to despair. When one of the team shot him with the starting pistol rigged to fire live ammo I fell at the same angle as he did.

Jon Plowman: 'No idea Twenty Twelve would be so real'

In essence, Twenty Twelve is an office sitcom, based around ordinary people who happen to be doing something huge.