Fresh Prince of Bel Air star Will delivered an impromptu performance of his 1991 hit 'Summertime' by literally grabbing a mic and jumping on his seat to perform!
Lewis had the best seat in the house too, as he was sat right next to Will.
Formula One ace Lewis told fans that he was invited to the event at Xen Lounge in Studio City by actor-turned-real estate agent Duane Martin and his wife Tisha Campbell-Martin, who is best known for playing Janet 'Jay' Johnson-Kyle on My Wife and Kids.
Lewis, who is dating former Pussycat Doll Nicole Scherzinger, said: "Hung out with my brother Will last night @ open mic party our friend Duane was having.
"Will got up on his seat & performed his classic song 'Summertime'. Now that's a night I won't forget... #WillSmith #badboys #openmicnight."
Err, where was our invite?!
Lewis posted a short video to Instagram of Will performing, but we wonder if Lewis delivered an impromptu rap of his own? The 29-year-old has always loved music and spent the past year in the studio recording tracks for fun.
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