A gorilla suit
A lion was getting rather old and slow and having difficulty catching its prey.
It decided it needed a disguise so that other animals did not know it was a lion and would not run away. So it goes into a fancy dress shop and buys a gorilla suit.
It then heads for a watering hole to see if it can catch something with its new disguise. On the way it comes across two eagles sitting on a rock.
One eagle says to it "Hi, Mr. Lion!" The other said, "Where did you get the gorilla suit?"
The lion, rather frustrated, asks, "How did you know I was a lion?"
The eagles then started to sing, "You can't hide your lion eyes".