Testing out Burger King's McDonald's penny Whopper deal -- does it work?

So, there's a story going around on social media that if you go to McDonald's and order a Whopper (which is only sold at Burger King)....you can get it for a PENNY. Is it true?
Published: 6:50 PM EST December 5, 2018
Updated: 4:08 PM EDT October 19, 2019