We were promised wet.

If you come to Austin City Limits Music Festival regularly, you know that the most reliable act is not Asleep At the Wheel, but the heat. It's hot. It's Texas hot. Death and taxes and sweating at ACL Fest.

But on Saturday of the festival's second weekend, it might have seemed a little hotter, just because previous forecasts had given music fans a gasp of hope, even if that hope was in the form of rain. By 4:15 p.m., there wasn't much hope, but there was some gasping.

Over at the American Express stage, where Metallica was scheduled to perform at 8 p.m., a set from rock trio Highly Suspect had been canceled because of an injury, leading to confused murmurs instead of gasps.

"Unfortunately, Highly Suspect will be unable to perform their set today, due to an injury in the band," the festival's Twitter account tweeted earlier in the day. "Catch an encore performance from @slenderbodies, 4:15p-5:15p on the American Express Stage."

Slenderbodies, a Los Angeles duo of slender men grooving out to late-night seduction jams, had played the HomeAway stage at noon. It seemed like many in the crowd hadn't seen the message about the change of plans (including this writer). A few fest-goers, including the man next to me, filed out in short order, but the band held the attention of the majority. Maybe "Enter Sandman" devotees staking out an early spot. Then there was that one guy, who when invited by the band to sing along to a song, raised his voice to say "We don't know the words!" (Joke was on him: It was a cover of Britney Spears' "Toxic," just smooth enough to not seem like a Flight of the Conchords sketch.)

A couple members of the security staff sprayed people with water from twisted-up plastic bottles. The audience waved their hands when they were supposed to. The sun had them slipping under.

Back out in the middle of the park, the slinky grooves swirled faintly as festival attendees laid on the ground like lizards, bathing in heat that made you question their choices. A hydration station line near the American Express stage was held up by a man carrying a giant orange water cooler, the kind you find at a football game and that usually gets filled with Gatorade instead of three different ACL Fest water spigots.

Every body, slender or otherwise, was slick with a sweat that they might wished was rain, after all.

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