They're both politically charged provocateurs known for whipping up controversy over the airwaves, so you'd think a radio confrontation between the two would end up being a verbal dust-up to remember.
But when Russell Brand interrupted the right-wing mouthpiece's live show yesterday, it all just ended up being… awkward.
The comedian charged into the studio while Hopkins was listening to a man named Paul speak his mind on the topic of (surprise surprise!) Islam.
The radio host tried to shoo Brand away as he moved about outside the studio, before Brand charged in.
Brand said: "Sorry Paul for interrupting you. Hello Paul from Croydon, carry on mate, didn't mean to interrupt but Katie did actually invite me in ..."
"It's so easy how these misunderstandings can occur," said Russell
"Russell Brand, would you mind leaving my studio and I will deal with you after, you naughty child?" said Hopkins.
"Would you mind moving? We're going to go to the news whether you like it or not. Can we please cut Russell Brand's mic? Russell Brand, out, out with you. Thank you for getting the Tory government into power and goodbye."
And then that was that. Guess this inevitable battle will have to wait for another day.