Related Clues:

• He was the first rapper to gain a UK Top ten hit
• 'Mama Said Knock You Out' singer
• 2012-16 host of the Grammys
• Rapper-turned-actor in "NCIS: Los Angeles"
• Rapper-turned-actor in 'NCIS: Los Angeles'
• Rap artist whose hits include Rock the Bells and Mama Said Knock You Out
• "Going Back to Cali" rapper