Get the tissues ready.

This video captures the amazing moment a circus lion was freed, after living 13 years in captivity.

The lion, named Will, was kept in a cage for almost a decade and a half in Brazil, where he performed as a circus animal.

When he was released onto grass, he was first unbelieving, and then acted just like a big cat, playing in the grass, pawing the ground and leaping for joy around his new open surroundings.

Animal rights organisations regularly protest the practice of using exotic animals in circus acts, and videos like this show just how meaningful it is for them to be let back into their natural environment.