How did they do the special effects for You & I???Like Harry and Zayn's special effect for example...when Harry turned around Zayn appeared.So please tell me how they did those special effects.

Oh you mean when they all morphed into each other.That part was amazing and I think the director and editor must have used a special type of computer to make the guy's images,I'm not really sure.And if you want to know what those frozen figures of them were,they're called freeze frames.

The director and the editor must've used maybe a special computer and used their images to make it look like they turned into each other.