Some call 'Doctor Who' a children's programme. Well, I salute the child who could get to grips with all the colour, plot twists and metaphysics on display in 'Day of the Doctor', surely Steven Moffat's most ambitious outing to date.
What he successfully managed to do was provide us with a ripping yarn in its own right, while doffing his cap to the fifty years of the Time Lord that had gone before, with enough half-century in-jokes - Bad Wolf, anyone? - to please the most demanding of the millions of fans watching in 90 countries around the world. I was curled up in the armchair, but can just imagine the cheer that went up in cinemas when Rose Tyler first appeared.
Three Timelords unite for the 50th anniversary of 'Doctor Who'
But first, a blue sky on a bright London day. Clara (Jenna Coleman) hard at work in a school classroom, until she is summoned, Matt Smith is hanging from the police telephone box somewhere between the Gherkin and the Eye, and we were off… to the National Gallery, and…
The last day of the Time War, watched by a man with "more blood on his hands than any other". Time for John Hurt's husky tones, Billie Piper's saucy retorts and proof that, with the right script, a pretty ingenue can match a screen veteran line for line. Before, we were whisked away to…
Rose Tyler, one of the familiar faces in 'The Day of the Doctor'
Elizabethan England, and - more cinema hoo-ha - David Tennant, as laconically wonderful as ever, riding the role like a bike he never got off, engaged in hillside romp with the Virgin Queen and making me lament again that the witty Scottish actor ever felt the need to prove his range beyond the Tardis... Hamlet Schmamlet.
Ah, but that's unfair to Matt Smith, back in the 'real' world of now, and having as much fun as ever with a bunch of new, befuddled, bemused recruits. "Someday you could just walk past a fez…" suggested Clara, although true Moffat-ites will recognise a colourful plot device when they see one.
With so much to pack in between Tudor times, the 'Black Archive' under today's Tower of London and the ultimate battle, the only frustration was that our favourites had to split up often to cover the ground. Thus, we had to wait quite a while to get much of the lovely chemistry between Coleman and Smith, and didn't get much from Tennant and Piper's poignant reunion.
John Hurt takes his place at number nine in the complete line-up
But Moffat more than compensated with what WAS in there. All the touchstones - scary monsters, plucky young heroine straight from Scooby Doo central casting with big specs and only a long MULTI-COLOURED scarf for comfort. The flirty banter between the three doctors - "chinny", "sandshoes" and "mid-life crisis" was on top form, the companions were knowing and irreverent, but none of this undercut the moving nature of the Doctors' dawning, horrible realisation of how they have been shaped by a horrible history. All this and production, costume and colour, in both contemporary 3D of present and squeaky machines of past.
All the way through came some delightful hat-tipping to the 50-year journey they, and we, have travelled. "Is there a lot of this in the future?" John Hurt asked Matt Smith, as David Tennant kissed the Queen. "There is a bit, yes," confirmed Smith, almost apologetically. Did you see what they did there? In the middle of celebrating a 50-year franchise, THAT's confidence.
But, even MORE clever than all of the above, was the demonstration of just how long this has all been in the planning. Remember Christopher Eccleston's references to the Time War in the very first days of the reboot? Here's proof that 'Doctor Who' supremos have been building to this moment from that long-ago day when Russell T Davies first put pen to paper and no one even knew if they had a fresh hit on their hands - unless they had a time machine, obviously.
Moving, surprising, multi-layered... what more could you ask of a TV show?
'Day of the Doctor' then, was the culmination of a drawn out creative achievement on a scale as epic in the planning as in the mischievous, moving, masterful results. With a flash of Doctor future, a tantalising glimpse of Mr Capaldi's furrowed brow, and, when we thought we needed no more, a blast of delightful Doctor past, with the unmistakable Baker bellows.
All in all, not bad for a children's programme.