It was during an exchange of words about racism and police brutality that a black fly suddenly landed on Vice Presidential candidate Mike Pence's white hair.
It stayed there for about two minutes, before flying on.
Mike Pence did not seem to notice the fly, but on social media it got all the more attention.
It did not take long before the fly had its own Twitter account.
"Everyone is jealous because I have the best seat during tonight's debate," @MikePenceFly tweeted.
The joke about the fly then continued to flow in on Twitter.
Photo: Twitter
Photo: Twitter
Photo: Twitter
Democratic presidential candidate Joe Biden also could not refrain from commenting on the incident and tweeted a photo of himself with a fly swatter in his hand.
Photo: Twitter
Even Mike Pence's own party was joking.
One of the Republicans' most famous senators, Rand Paul from Kentucky, tweeted that the fly was a way to monitor the vice presidential candidate.
Photo: Twitter