If you're not all that familiar with Mel Gibson's father, "Last Week Tonight" host John Oliver would definitely recommend checking out the man's Wikipedia page. The HBO host was simply stunned by it on Sunday night.

John Oliver made a jab at the expense of Mel Gibson — and the actor’s father — on Sunday’s Last Week Tonight. The HBO late-night host recapped the news about Liz Oyer, a U.S. pardon attorney who wrote an opinion column for Rolling Stone last week theorizing about why she was fired from her job.

John Oliver sounded off on a Justice Department official’s claim that she was fired for refusing to recommend that Mel Gibson’s gun rights be restored, saying that the “Mad Max” and “Braveheart” actor is “best known for his work in screaming.