Will Smith has smacked presenter Chris Rock in the face with an open hand and shouted a vulgarity at the comedian for making a joke about his wife's appearance at the Oscars ceremony.
Rock made a joke about the hairstyle of Smith's wife Jada Pinkett Smith that referenced the movie G.I. Jane, in which actress Demi Moore shaved her head.
Smith stormed onto the stage and slapped Rock in what at first appeared to be a scripted joke.
But the mood turned sombre moments later when Smith, back in his seat, twice shouted back, "Keep my wife's name out of your f***ing mouth".
A clearly shaken Rock went on to present the award for best documentary feature to Summer of Soul (Or, When The Revolution Could Not Be Televised).
In a bizarre and bittersweet turn, Smith soon returned to the stage to accept his Oscar for Best Actor, which he won for his portrayal of Richard Williams, the father of tennis greats Serena and Venus.
"I look like the crazy father, just like they said about Richard Williams," said Smith, referencing his character.
"But love will make you do crazy things.
"I'm being called on in my life to love people and to protect people... In this business, you've gotta have people disrespecting you, and you've got to smile and pretend that's okay.
"I want to be a vessel for love. I want to say thank you to Venus and Serena and the entire Williams family for entrusting me with your story.
"That's what I want to do, I want to be an ambassador for that kind of love, and care and concern.
"I want to apologise to the Academy, I want to apologise to all my fellow nominees."
