Can the garden-party idyll of the newly restored film Jazz on a Summer’s Day be recovered in the age of COVID and BLM? Of course not—but this year’s festival should be paradise enough. Boss and bassist Christian McBride has plucked from the fields of jazz, pop, and soul a cornucopia of talent, ranging from presbyters like Mavis Staples, Dave Holland, and Charles Lloyd to up-and-comers such as the pensive saxophonist Immanuel Wilkins, the public-defender-turned-belter Danielle Ponder, and the guitarist Cory Wong, whose fizzy, funky “elevator music for an elevated mood” would surely cause numerous gluteal collisions between floors. —E.E.