Pharrell Williams famously created a 24-hour music video for his insanely catchy track "Happy".
Apparently just for a bit of fun, Dutch ad agency House of Halo has now removed the tune from the video and dubbed in people singing along.
The video is kind of haunting and impressively, still uplifting.
It also bizarrely features Sinead O'Connor's "Nothing Compares 2U" and Robin Thicke's "Blurred Lines".