Today we begin our series Summer of Soul, featuring interviews from our archive with some of the performers showcased in the documentary 'Summer of Soul,' about the 1969 Harlem Cultural Festival. The festival was a series of six concerts that reflected changes in Black music, culture and politics. Over the next few days, we'll hear interviews from our archive with B.B. King, Hugh Masekela, Gladys Knight, Mavis Staples, Max Roach and Abbey Lincoln. We start with Ahmir "Questlove" Thompson, who directed the documentary. Questlove founded the band The Roots, the house band of 'The Tonight Show' and is known for his encyclopedic knowledge of hip-hop, funk, soul and R&B. Justin Chang reviews 'Shang-Chi,' Marvel's first superhero film starring an Asian lead.