Jimmy Kimmel's fans are shockingly funny.

The late night host asked viewers to sneak up on their dads and shout "I love you" to their unsuspecting pops as part of his annual Father's Day YouTube challenge. The results? He showed them on Monday night's show and they were nothing short of fantastic, as dads were surprised in the bathroom, in bed, on the golf course and by the pool, among other places.

Over on The Tonight Show, Will Ferrell stopped by to chat with his former Saturday Night Live co-star, Jimmy Fallon. These two have a long history, of course, so you'd expect them to feed off each other. They didn't disappoint, especially while playing a riveting game of Think Fast!, in which, according to the YouTube description, they had to "take turns asking each other random questions and immediately answering them with the first thing that pops into their heads before time runs out."

The Late Show's Stephen Colbert kept things topical in his cold open with a little joke about Amazon's acquisition of Whole Foods. If you've ever ordered anything from Amazon, you'll get it. Heck, even if you haven't you'll still chuckle.

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