The 11th annual Lollapalooza rolled through Grant Park this weekend, and with it came 300,000 fans, 140 bands, one severe thunderstorm warning, and seemingly endless swarms of dragonflies. Millennials raved; boomers swayed; sleeveless Metallica shirts abounded. The weekend's best and worst moments, below.

The Best

Sir Paul plays the classics

Paul McCartney Lollapalooza 2015
Sir Paul McCartney at Lollapalooza on Friday  Photo: Chris Sweda/Chicago Tribune

For all the fear that Paul McCartney's Friday night set would be a tedious reliving of his four-decade solo career (some of it from this magazine), the 73-year-old delivered one of the best performances of the weekend, perhaps even the year. Backed by an impressive light show and rotating images from his heyday, Macca powered through a set of McCartney-Lennon classics ("Let It Be," "Hey Jude"), toasts to his late bandmates ("Something," "Being for the Benefit of Mr. Kite!,") and a few curveballs ("Get Back" with Alamaba Shakes's Brittany Howard and "We Can Work it Out" mashed up with his Rihanna/Kanye-collab "FourFiveSeconds"). There were Wings songs, of course—"Live and Let Die" got the pyrotechnic treatment it always deserved—but the night was, at its core, a dedication to the beloved Beatles.

The fest's air-tight disaster plan

It wouldn’t be a Lollapalooza without a rainstorm, and this year’s festival was no exception. Thankfully, Sunday afternoon’s storm was brief and fest organizers evacuated the crowds in a timely and (relatively) efficient manner. Most people were able to leave with enough time to stay dry until the park re-opened. Once it did, no artist was left behind as shortened festival sets ensured every performer got a chance to make it to the stage.

Flash tats are now a thing

Floral crowns are out and flash tats are in. The festival hippie has given way to the futuristic metallic warrior. It’s subtle. It’s cool. And it doesn’t require more than a dollar or two to execute. Nice!

TV on the Radio and Florence + the Machine under the threat of rain

There may not be two acts better suited to pre-storm mania than this back-to-back pairing.  Anchored by singer Tunde Adebimpe's manic urgency, TV on the Radio sounded borderline apocalyptic as the fast-moving front blew in and kicked up whirling clouds of dust from Hutchinson Field's softball diamonds. As for Florence Welch, it would not have been surprising to learn that she had conjured the lightning storm that backed her set all by herself, so perfectly suited was her plaintive wail to every crashing bolt.

Chicago shows up for Mick Jenkins

At a festival whose crowd often shows more reverence for raging than actual live music, it was refreshing seeing a full house at rapper Mick Jenkin's 11:45 a.m. set Saturday. The Burnside-raised MC skittered through a flawless mix of heady tracks from his mixtape Water[s] and lighter fare from his forthcoming EP Wave[s], effectively kicking off Lolla's second day with a breakfast of fibrous brainfood.

Brittany Howard breaks the PA system

Everybody knows the Alabama Shakes frontwoman has got major pipes. Still, to see her use them in glorious, uninhibited fashion as she did Friday evening was a sight to behold. She crooned, she pleaded, she begged, she screamed, she howled—she broke the PA system. (Or at least took ownership of the matter as the sound guys worked frantically to fix it). Even Mayor Emanuel, standing coolly on the left side of the stage, seemed impressed. He stayed for the whole set.

Pell arrives

This year's sleeper star on the BMI stage was Pell, the spunky 22-year-old rapper who grew a crowd of two-dozen sun-sick loafers into a full-on party, complete with stage-dives, a cameo by G-Eazy, and a resounding full-house chant of his stock tagline, "Pell yeah."

Amelia Meath's moves

The Sylvan Esso singer has spoken before of her reverence for dance, and she backed up her claims on Friday night during a well-populated set where she twisted, twirled, and high-kicked through forty-five minutes of synth-pop. Oh, and she did it in six-inch platforms.

Vic Mensa makes the most of the weekend

For someone not actually listed on the lineup, the Roc Nation rapper was all over Lollapalooza, popping up at DJ Dillon Francis and rappers G-Eazy and A$AP Rocky's sets to perform his single "U Mad" on Friday, Saturday, and Sunday respectively. On Friday, he made a ridiculously unsafe entrance. And on Sunday, he and A$AP moshed to "U Mad," House of Pain's "Jump Around," and Nirvana's "Smells Like Teen Spirit." On the off chance Lolla's millennial crowd only knew of Vic tangentially, this weekend put him front and center.

Zebra Katz kills it

Zebra Katz took to the stage at a super-early 1:10 p.m. time slot on Sunday. It was the peak of the day’s humidity, but that didn't stop Katz from grinding on the stage and eventually running off of it to mingle with enthusiastic fans. “I love you. I love you. I love you,” he repeated at the end of his set. It was obvious the crowd loved him right back.

Owen+Alchemy gets into the fest business

It’s easy to indulge (in a variety of different ways) at any music festival, but Lolla makes it something of a requirement. Chowtown’s abundance of gourmet goodies quickly fills you up. But thankfully, Owen + Alchemy was there to help settle stomachs with their ice-cold pressed juices. A blackberry, basil and lemonade is 10 times more satisfying than a cheap and bloat-inducing beer.

Yes, please!   Photo: Kristan Lieb

Ice cream!

Lines for ice cream vendors were at least triple the length of those for any other food, even though scoops liquified after just a few minutes in the sun. This is why Yoberri's root beer float came in handy—the soda served as built-in insulation.

The Worst

Metallica's stage show (or lack thereof)

Metallica's brand of pointy-guitar metal hasn't exactly aged gracefully into this century (see: Rob Trujillo's bass solo). The band could have mitigated the problem with some big-box theatrics a la McCartney's set on Friday. Instead, the band chose to broadcast itself on all three panels of Lolla's main-stage Jumbotron, the effect of which was a triple exclamation point to their declaration of loud/fast/heavy.

Metallica Lollapalooza 2015
Metallica on Saturday night   Photo: Kristan Lieb

Kaskade bleeds into Paul McCartney

The bleed from Perry’s stage this weekend was just as bad as in years past, but it was especially irritating while listening to Sir Paul’s long and loving Friday night set. Why couldn’t the EDM bangers be saved for earlier in the evening? Isn’t that genre on its last leg anyway? Unfortunately, many McCartney fans were treated to two sets all at once.

Travi$ Scott

Who would have thought the G.O.O.D. music MC would be responsible for the fest's most chaotic moment? Minutes after coming onstage, Scott ordered his crowd to climb over the security barrier, and, like lemmings, they did. Mayhem ensued, Scott was arrested for disorderly conduct, and now there's ample fodder for anyone trying to argue that hip-hop instigates violence. A lose-lose situation.

Father John Misty's meta-meta-dejection

Baltimore singer Josh Tillman has built an empire around his parodic onstage alter-ego Father John Misty, and due to vocal problems Friday afternoon, the character's sarcasm was in overdrive. Tillman's banter included mocking Lolla's corporate sponsors, trashing his own 3:30 p.m. time slot, and at one point skipping a verse of "When You're Smiling and Astride Me" to riff on a flyover Trojan advertisement. It was funny stuff to be sure, but at base level, conveyed that Tillman wanted deeply to be elsewhere.

The sun

Words to describe this weekend's heat: ridiculous, horrible, pulverizing, UGH.