Viewers saw their revelation on last night's episode when Alfonso was telling his campmates about appearing in a 1985 television production called Night Of 100 Stars II<.em>.
"I was there!" shouted an excited David. "I was in the fashion section finale with Ann-Margret and The Rockettes and they put us up at the Hilton… My God, we performed together!"
Alfonso, who is most famous for his role as Carlton in The Fresh Prince Of Bel-Air, seemed equally excited, saying: "We have already done this!"
After exchanging a hug, Alfonso said: "It's crazy to think we actually worked together on the same stage, same night… to find that out in the Australian jungle is pretty far away."
David said: "These moments are wonderful and special and revealing more and more. Very interesting."
Meanwhile, on last night's episode, viewers saw Joey Essex and Matthew Wright being selected again for a second Bush Tucker Trial.
There is no I'm A Celebrity tonight because of the England/Germany game but it returns to ITV on Wednesday.
Check out the full I'm A Celebrity 2013 lineup below: