When Will Smith and son Jaden appeared on 'The Graham Norton Show' across the pond to promote their film 'After Earth,' the elder Smith deemed his son "a very good rapper" and even though they've not recorded together, he suggested, "maybe one day we'll do something."

The "one day" was that day, as the father-son twosome engaged in an impromptu rap where Will beatboxed as Jaden spit rhymes. Smith's cohort DJ Jazzy Jeff was in the hizzy and they were eventually joined by Alfonso Ribeiro, Will's former co-star on 'The Fresh Prince of Bel Air.' Ribeiro did his famous Carlton dance to Tom Jones tunes.

It was a flawless five minutes, as fellow guests Bradley Cooper and Heather Graham looked on, the latter getting totally grooving in her seat.