It is Valentine's Day 2014. Through some combination of luck, cash and industry connections, you are one of just 420 people attending an intimate Prince show in London that was announced only hours earlier.

Amazingly, instead of keeping everybody waiting until the wee hours of the morning, Prince takes the stage shortly after 9PM for a two-hour show. Accompanied only by 3rdeyegirl drummer Hannah Ford - who according to The Guardian was using a soap box as a drum - he begins playing acoustic versions of hits like "Take Me With U," "Raspberry Beret" and "U Got the Look."

Then suddenly, he starts playing a song by the Clash. And not just any song, but "Train In Vain," the unbelievably infectious last-minute addition to their 1979 masterpiece London Calling. It's a more logical fit than you might think on first blush. After all, Prince spent much of the early '80s stripping pop, R&B and funk down to their bare essentials just as the Clash did to rock and roll with their first records.

London Calling was also the album that proved beyond a shadow of a doubt that the London-born punk-rock pioneers refused to be confined by any genre or classification - a spirit Prince could most definitely relate to.

And it sounds absolutely amazing. You wouldn't want any more instruments or singers to join in, the spare arrangement reveals just how perfect Prince's voice is for this song. He radiates a sense of joy and yet still captures the heartache at the core of the lyrics. This is truly a magical moment.

The only problem - as the above YouTube clip quite clearly attests - is that rather than truly absorbing and enjoying this performance - which literally only ever happened four times ever - you, your friend and several other people in the crowd talked through the entire thing. Nice job!

(Try to) Hear Prince Covering "Train in Vain"