Metallica and Paul McCartney have been announced as the headliners of Lollapalooza 2015. The festival takes place between July 31 and August 2 in Chicago's Grant Park. They're playing different nights, so sadly the "Helter Skelter" jam session you're already dreaming about is probably not going to happen.

According to Lollapalooza's official site, McCartney will headline the Friday night lineup, which also features the Weeknd, Alt-J, Alabama Shakes, Kaskade, Dillon Francis, Gary Clark Jr., Flying Lotus, Hot Chip, the War on Drugs, DJ Snake, Sylvan Esso, MS MR, Tove Lo, Glass Animals, St. Paul & the Broken Bones, First Aid Kit, DJ Mustard, James Bay, Broods, MisterWives, What So Not, Sxa, Jamestown Revival, Philip Selway, Young Thug, Coasts, Destructo, Borns, Badbadnotgood, Mighty Oaks, Bear’s Den, Peking Duk, Black Pistol Fire, Spookyland, Bully, Gabriel Garzon-Montano, Kyle Thornton & the Company, The New Pacific, Daye Jack, The Pop Ups, Q Brothers, School of Rock AllStars, the Jimmies and Mista Cookie Jar and the Chocolate Chips. McCartney's most recent studio album was 2013's New, but recently he's made headlines for a series of collaborative singles with hip-hop star Kanye West.

Metallica – who are reportedly and hopefully hard at work on the long-awaited follow-up to their last studio album, 2008's Death Magnetic – will be atop the bill Saturday night. Tame Impala, Death From Above 1979, Sam Smith, Alesso, Kid Cudi, Brand New, Carnage, G-Easy, Walk the Moon, Tyler the Creator, the Tallest Man on Earth, Banks, Chet Faker, Sturgill Simpson, Toro y Moi, Charli XCX, Django Django, Boys Noize, Delta Spirit, RL Grime, Givers, Ryn Weaver, Travi$ Scott, Caked Up, Hermitude, Wet, Holychild, Catfish and the Bottlemen, Zella Day, Mr. Eden, Jessica Hernandez & the Deltas, Snbrn, Ellie King, Beat Connection, Mick Jenkins, Raury, Jack Novak, Pell, White Sea, Hippo Campus, Coin, Danny Weinkauf, School of Rock Allstars, The Jimmies, Mista Cookie Jar and the Chocolate Chips and the Helmets will also appear.

The Sunday night lineup is headlined by Florence + the Machine and also features Bassnectar, Of Monsters and Men, A$AP Rocky, TV On The Radio, Nero, twenty one pilots, Nicky Romero, Kygo, Marina and the Diamonds, FKA Twigs, Lord Huron, Gogol Bordello, Stromae, Odesza, Logic, The Chainsmokers, Wild Belle, Twin Peaks, Angus & Julia Stone, George Ezra, Strand of Oaks, Moon Taxi, Shakey Graves, Galantis, Night Terrors of 1927, Alison Wonderland, Circa Waves, DMAs, Sheppard, Mako, Skylar Spence, the Wombats, Halsey, Lion Babe, Black Tiger Sex Machine, Vérité, Jacklndn, Zebra Katz, the Lonely Biscuits, SirenXX, In the Whale, Atarah Valentine, The Pop Ups, Danny Weinkauf, Motown Pete, Q Brothers, and the School of Rock Allstars.

Three-day passes for Lollapalooza 2015 are already sold out. Single-day passes, priced at $110, go on sale today at the festival's official website.

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