It’s the bizarre video that has attracted more than 1.8 million hits on YouTube.
Unsuspecting viewers are invited to count how many times basketball players pass the ball to each other. But – halfway through – a person in a gorilla suit walks through the middle of the players.
Incredibly, scientists discovered that of the people who watched the video who were able to count how many times the basketball was passed, as much as 40 per cent failed to see the person in the gorilla suit.