How Eric Stonestreet Pranked His Girlfriend for Two Months With This Awful Mustache

Ellen DeGeneres loves a good prank, but she's never gone as far as Eric Stonestreet did in punking his girlfriend the summer before "Modern Family's" tenth season.

The "Secret Life of Pets 2" star shared his elaborate prank with Ellen because he knew that perhaps no one would appreciate it as much as the queen of scares. Ad she was appropriately in awe.

Ellen already had an appreciation for Eric's panache for messing with those he cares about as he's been doing it and sharing it online for years. Sometimes it's as simple as tricking his girlfriend into thinking he's taking a lovely beach-side photograph when he's actually taking video. The classics never die.

But his greatest achievement so far was another one he played on his long-suffering girlfriend and it's all about an epic handlebar mustache. "She hated it," Eric laughed.

So first, he grew it out and made her deal with looking at it. But that wasn't enough. "Then I convinced her that 'Modern Family,' the writers, they saw my mustache and they loved it," he told Ellen. "And they said, 'You know what? We want Cam to have that mustache in the season premiere.'"

Perhaps because she knew he was a notorious prankster, or perhaps just for the joy of it, Eric even recruited some friends in on this one to really sell it. "I had the creator Chris Lloyd, one of our executive producers send me fake emails saying, here's our story ideas for the mustache. She's like, 'You have gotta be kidding me.'"

At this point he'd convinced her he had to wear the mustache through the rest of the summer break from filming so he could have it for the premiere, so he carried on like this for two straight months.

"The night before 'Modern Family' started, I got up in the middle of the night and shaved it off," he said. "And then just woke up and she wakes up in the morning and looks at me like, 'Your mustache is gone.' I'm like, 'What? Are you kidding me? Are you serious? What do you mean? Oh my god! I sleep-shaved!'

That's right, two months of dealing with that awful, awful mustache, "all just for that moment." That is commitment to your craft, good sir. A true artisan of the prank, it's no wonder he seems to recognize Ellen's pranks when he runs into them at the supermarket ... which has happened more than once now, apparently.

Later in the show, Ellen decided to pay tribute to Eric's performance in "The Secret Life of Pets 2" by having the "Modern Family" star see how well he could identify different items while blindfolded using only his tongue.

But really, she wanted him to really get in there because when he was struggling on the first one she chastised him for "not trying that hard" and convinced him to suck the whole object into his mouth.

"If it's somebody's mouth guard, I'm gonna be real mad," Eric shot back, spitting it out. It was fake teeth, so he was close!

He had no trouble with Jell-O or even a stuffed animal of his character from the film, but one object let him completely stumped and a little grossed out.

"It's like wet and moist and there's no flavor and that's weird because I'm touching it and my tongue's telling me it should taste like pudding," he said, and yet it was not pudding. Find out what stumped him in the video above.

Then check out Eric Stonestreet in "The Secret Life of Pets 2" this Friday in theaters, and on the final season of "Modern Family," launching this fall on ABC.

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