20 Mind-Blowing Facts About It's Always Sunny In Philadelphia

10. It Was Rob McElhenney's Idea To Become Fat Mac

At the start of season seven, the formerly Ronald 'Mac' McDonald gains around fifty pounds of pure fat. The weight gain was originally meant to be muscle mass as Mac wanted to go from a 'tiny twink to a muscle-bound freak' but things went horrible awry. It was an interesting development for the Mac character and provided a lot of hilarious moments throughout the season as the gang incessantly mocked their obese friend and Mac was seen gorging on chimichangas and rum ham. The weight gain was all down to Rob McElhenney, who decided to gain the weight against the wishes of the rest of the cast. He basically just thought it would be funny if Mac got fat (he was right) and went about eating and drinking everything in sight. Amazingly Mac shed all of the weight when the season had finished shooting and went back to being regular Mac next season. One of the funniest parts of Fat Mac was his constant referring to the weight gain as 'cultivating mass' as he believed he was actually gaining muscle and looked better. https://www.youtube.com/watch?v=WhD14Jvey44