'SNL' Recap: Leonardo DiCaprio, Jonah Hill Reenact Romantic 'Titanic' Scene (Video)

Leonardo DiCaprio Jonah Hill SNL - H 2014

This is why you don't talk about Leonardo DiCaprio behind his back -- because you never know where he might be.

Jonah Hill learned that the hard way on this week's Saturday Night Live. The host, hot off an Oscar nomination for The Wolf of Wall Street, attempted to tout his own acting chops by putting co-star DiCaprio down, claiming (among other things) that Martin Scorsese was thrilled to have Hill join the film, but reluctant to add DiCaprio.

But things got awkward when DiCaprio showed up in the flesh (to big applause), revealing he'd been backstage the entire time. He gave Hill a fatherly talk about not letting his second Oscar nomination go to his head.

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"Jonah, I knew this was going to happen if you got nominated. But you don't have to pretend anymore. You're a real actor now. You should be humble, you should be gracious," DiCaprio lectured.

The kicker came when DiCaprio offered to comfort Hill by playing out a famous scene from Titanic. Hill took on Kate Winslet's role, and truly looked like he was king of the world in DiCaprio's arms.

In perhaps the best segment of the night, Hill parodied Spike Jonze's Her -- playing a man whose OS had his voice and personality. Me culminated with a guest appearance from Michael Cera, playing a man the OS hired to work as a surrogate so the two could -- ahem -- get it on. Talk about self love.

Surprisingly, SNL didn't have much to say about Justin Bieber's recent DUI arrest. At the top of Weekend Update, Seth Meyers showed Bieber's smiling mug shot and said, "This certainly looks like the face of a guy who has learned his lesson." Later, Kenan Thompson played the Miami Beach police officer who pulled Bieber over, and noted the pop star's behavior wasn't so bad by the city's standards.

"It's the only city in America where NBA players are the best behaved people," Thompson said.

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Oscar nominee he may be, but Hill didn't shy away from his crass comedy roots. In a couples quiz show sketch, he was forced to admit he'd clogged a toilet (twice!).

In another, he played a young man freaking out while at dinner at his boss' place. When he complimented the boss' wife on her delicious Cobb salad, he lost his cool when informed it was actually Waldorf salad. He excused himself to use the restroom and had a tantrum -- but the dinner guests could hear his yelling.

"You're blowing it! Cobb salad! It's a freakin' Waldorf you idiot!"

It went on like that for minutes, with Hill losing it after getting various dinner conversation details wrong.

Saturday Night Live returns next week with host Melissa McCarthy and musical guest Imagine Dragons.