Christoph Waltz had to see a medic on the set of Horrible Bosses 2 after he fired a gun too close to his head.

The Django Unchained actor plays an evil businessman who backs out of an investment, prompting the lead trio - played by Jason Sudeikis, Jason Bateman and Charlie Day - to kidnap his son to get their money back via a ransom.

During the shoot, Waltz was left with ringing in his ears because he forgot to keep his weapon a safe distance away from his head when he fired it during a gun scene.

His co-star Day tells Wenn, "Christoph Waltz injured himself the most. He shot off a gun and it was too close to his ear and he had to see a doctor cos his ear was ringing."