Kiss and Def Leppard kicked off their 40-date summer tour last night (June 23) in Salt Lake City, Utah. As you'd expect, the set lists were largely packed with famous songs such as 'Photograph' and 'Rock and Roll All Nite.' But both groups, particularly Kiss, also had some surprises in store for the crowd.

Def Leppard kicked off the night with a blast from early in their career -- 'Let It Go,' the opening track from their 1981 album 'High & Dry.' Later on, they also broke out an acoustic version of 'Bringin' on the Heartbreak' and the instrumental 'Switch 625' from that same album. The latter selection, a tribute to deceased guitarist Steve Clark, has been a welcome addition to the band's shows in recent years.

Otherwise, Def Leppard's set list was largely devoted to the massive, must-play hits from their two best-selling albums: 1983's 'Pyromania' and 1987's 'Hysteria.' Dan Nailen of Salt Lake magazine had high praise for the group's performance, declaring that "both 'Rock of Ages' and 'Photograph' sounded as good now as they did when the lads were three decades younger."

Kiss seemed especially determined to shake things up this time around, forgoing traditional concert staples such as 'Deuce,' 'Lick it Up,' 'God of Thunder' and even the mighty 'Love Gun' in favor of a set list that cast a spotlight on some under-appreciated gems from their 40-year career. They returned 'King of the Night Time World' to show-opening status for the first time in five years, moved 'Psycho Circus' back to accompany singer Paul Stanley's nightly flight into the audience, and even dusted off the late '80s single 'Hide Your Heart' early in the set.

If the opening night is any indication, it would also appear that 'Makin' Love' and 'Christine Sixteen' have been promoted to full-time status following their frequent inclusions on the group's 2013 overseas tour. Nailen reports that Kiss "delivered what the fans love about them -- massive visual effects set to the sound of old favorites like 'I Love It Loud' and 'Shout It Out Loud.'

The Kiss / Def Leppard tour resumes tomorrow night in Denver and winds all around the country before wrapping up on August 31 in The Woodlands, Texas. You can get all the dates here.

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