Not often you'll hear me say this, but I wish I was in Germany.

Now before my girlfriend goes tonto on me for wishing to be elsewhere at Valentines, tonight something very special with my other true love is happening at the Brandenburg Gate in Berlin.

Metropolis is finally being for the first time in 83 years, being seen as Fritz Lang intended it.

My love affair with Metropolis goes back nearly two decades, although I was aware of it long before then. In fact, the first time I remember it was seeing the Mariabot on the opening titles to Tomorrow's World in the 1980s.

But it was a restored, non-Moroderised version of the film which aired late night on Channel 4, as part of a Sci Fi season back when the fourth channel was worth watching, that hooked me.

A strange, disjointed piece of cinema, thanks to the intertitles which tried to fill in and explain the gaps between lost scenes, it was still utterly compelling, thanks to the sheer beauty of the visuals.

At the time, it was the most expensive film Germany had ever produced, with a scale and scope that still held up 70 years later.

The story of the rise and fall of Metropolis has been told by far better, more learned people than me, but for the few who don't know it, here goes. Lang's original, 153-minute cut wasn't a massive success - a problem given it cost a packet to make - and foreign cinema owners were unimpressed with the idea of a film lasting 2 and a half hours. So it got hacked to bits by the studio, losing around a quarter of the film.

And that appeared to be that, until the 1980s when Giorgio Moroder proceed a new edit that shortened things further (although, to be fair, that was largely because he dumped the intertitles and ran it at 24fps, rather than the 16fps silent flicks usually run at). Frames were put through colour filters and a none-more-80s pop soundtrack was added. The result was, to say the least, controversial - here's the famous transformation scene, for example:

Now, I'll admit, I've still got a soft spot for Moroder's version, partly because I am a child of the 80s but also because it helped bring the film back into the public eye once again, and in many ways that visibility sparked the restoration that followed.

Then the FW Murnau Foundation managed to piece together everything held in archives, stills, intertitles and the original score to produce a new, 124-min edit which had been digitally remastered and cleaned up. I interviewed the archivist behind the restoration, Martin Koerber, for SFX at the time, having written the magazine's Past Perfect feature on the original movie. And it seemed, that would be as close as we'd ever get to Lang's original version.

And then last year came the news that pretty much blew everyone away. A negative of the original film turned up in Argentina. Not one of the hacked-to-bits studio prints from 1927, but as near as anyone could tell the original cut premiered in January 1927. After 80-odd years it was a bit of a mess, and one scene was damaged beyond repair, but apart from that - it was Lang's movie.

The team at FW Murnau got to work on restoring it into a watchable version. And tonight, free for what will likely be thousands of film fans from Germany and beyond, it will be screened in public for the first time as part of the Berlin Film Festival, with a live orchestral score accompanying the film as it was intended to be seen.

It'll also be shown at the Alte Opera in Frankfurt and the German arts TV station ARTE is airing it - along with interviews and packages on the restoration itself. The Deutchse Kinemathek film museum in Berlin is also holding a retrospective of the film. And the whole thing is also, it seems, being streamed live tonight on ARTE's website - there's still some debate over the translation of that, to be honest.
Not that I'll be put off from logging on to see, just in case.

And it's proof that dreams do come true. All these years of being a Doctor Who fan paid off, because as Who fandom knows only too well, there's no such thing as a truly lost story. The episodes of that show have a tendency to turn up in the unlikeliest of locations and at the most uncanny of times. Mormon churches, Nigerian TV stations, off the back of a lorry… they keep rolling back to the BBC.

So while I'd always presumed Metropolis was lost forever, I'd never given up hope that it might just happen. And this Valentine's weekend, that love affair gets to be rekindled again. Now, I wonder if it's too late to book a daytrip to Berlin...