Ritchson shared an Instagram post of the chance encounter, writing, "So our Reacher set got in the way of these legends." Ritchson's post featured a carousel of photos and videos

Former President Joe Biden and his family made a surprise cameo on the set of the Amazon action series Reacher on Monday morning. According to the show's star, Alan Ritchson, the ultimate alpha male showdown saw Biden proving his dominance over the burly actor with his own flex of strength.

The blockbuster action star shared a series of images of the impromptu meet-and-greet along with a joke that they discussed "string theory and quantum entanglement."