Most music festivals have more than one stage these days, but when it comes to scale, Lollapalooza has few peers: this year it’s booked nearly 150 acts on eight stages. It’s difficult if not impossible to see more than a small fraction of the weekend-­long bill, unless you’ve got access to a jet pack or teleportation technology—the northernmost and southernmost stages are nearly a mile apart, which would be a 15-minute walk even if you didn’t have to maneuver through a crowd of 100,000 people. The number of stages allows the festival to give every act a substantial set—nobody’s stuck with just 20 minutes—but it’s also pretty easy to entirely miss a band that’s playing for an hour. At least this situation is a win for Lollapalooza’s advertisers: you can’t navigate the park or the schedule without using the names of the companies that have sponsored most of the stages.

Friday, July 31

12:45-1:30 PM | SZA | Samsung Galaxy Stage

The young hip-hop nuts in jazz trio BadBadNotGood have embraced both sides of their identity. Last year they released their first album composed entirely of original material, the controlled energy wave III (Innovative Leisure), and immediately followed it with Sour Soul (Lex), a rap-first collaboration with Ghostface Killah. The band’s improvisations are just as inspired as their MC-friendly covers: drummer Alex Sowinski rarely repeats a measure, while keyboardist Matthew Tavares and bassist Chester Hansen know when to go all in and when to dial it back. Onstage, though, they always seem mere seconds from eruption. Also Thu 7/30 at Subterranean, sold out, 17+, and Fri 7/31 at Concord Music Hall with headliner Tyler, the Creator, $30, 18+. —Tyler Daswick

5:45-6:45 PM | Alabama Shakes | Samsung Galaxy Stage

Lollapalooza’s choice of headliners on Friday night feels like a choice between centuries. There’s digitally augmented crooner the Weeknd; experimental producer Flying Lotus, who has his own radio station in Grand Theft Auto V; and Paul McCartney, who wrote most of the songs he’ll play tonight between 1962 and 1982. Now 73 years old, he routinely plays for longer than the 135 minutes allocated to him at Lollapalooza, delivering more than 30 hits from the Beatles, Wings, and solo McCartney songbooks. YouTube evidence suggests that time has been kind to McCartney—he can still hit many of the high notes, and his hair and waistline haven’t changed all that much in a half century. Most important, his knack for crowd-pleasing showmanship remains intact. —Bill Meyer

1-1:45 PM | Holychild | Bud Light Stage