David Cameron was caught humming a little tune by TV microphones as he made his way back inside Number 10 after announcing when Theresa May would succeed him as prime minister.
After making a statement where he hailed May as "strong and competent", Cameron was picked up by an ITV microphone humming "Do-do-do-do" before saying: "Right!"
And predictably, the internet went into meltdown.
But what was he singing? Social media was full of suggestions:
What does it mean? Speculation was at rife:
And why was he singing? One guy had the answer:
And what now? The internet is demanding a dubstep remix:
Maybe there's a new career waiting for Cameron after he hands the keys to Number 10 to Theresa May.