At what could have easily been an intimate Summer Camp pre-party, a small crowd made up almost exclusively of members of the tightknit “Illinois Umphrey’s Crew” Facebook group gathered on a cool Chicago Monday night to watch Umphrey’s McGee guitarist Brendan Bayliss play a rare and extremely sold-out solo show. The dim and narrow Tonic Room could barely hold the crowd’s palpable excitement, much less the actual crowd itself, but Barry Brown – musician, long-time member of the Illinois Crew and Tonic Room bartender – compensated attendees by organizing a two-set show packed with pre-requested Umphrey’s favorites, original tunes, covers, several rarities and lots of booze.

After the lights dimmed over an eager and buzzed crowd, Bayliss took the stage, gazing out to some undoubtedly familiar faces. After a swift introduction from Barry and a request for his glass of red wine, Bayliss launched into “Similar Skin” and the crowd began its nearly-three hour sing-along. “If you guys could do the harmonies, too, that’d help,” Bayliss joked as he jumped into a version of “Puppet String” that was interrupted temporarily by his first cover: Bruce Springsteen’s “I’m on Fire.”

Bayliss appeared to be at the mercy of his adoring crowd of diehards, taking requests as they shouted them out. Much to the group’s delight, he took the bait for a rare rendition of “Alex’s House” – between “Cut the Cable” and 30db tune, “Backbone” – before reluctantly accepting a shot from a fan. “I’m only taking one, though – I have to take my kids swimming in the morning,” he warned with a mischievous smile.

Capitalizing on the atmosphere cultivated by the warm crowd, Bayliss seemed to turn the Tonic Room into his own experiment lab. He offered the crowd an unnamed original – just “something [he’s] been working on” recently – in the middle of “August” and even took a stab at Paul Simon’s “50 Ways to Leave Your Lover” despite his humble concern that he “might fuck it up.” The first set ended with “Hourglass” following a version of “No Diablo” that the crowd sang so loud, it was hard to tell if Bayliss was saying anything at all.

The guitarist was welcomed to the stage for his second set by the crowd’s loud and sloppy version of “Come Sail Away” by Styx, which Barry claimed in an unconvincing tone was one of Bayliss’ favorites. “Well, this is going to be anticlimactic – what do you do after Styx?” Bayliss laughed, before mentioning that his wife had to leave and he promised he’d play “You and You Alone” before she left. Vocalist Michelle Hallman was welcomed to the stage to add her powerful-yet-sweet pipes and a percussion shaker to a covers “Circle” by Edie Brickell and “Under African Skies” by Paul Simon.

Bayliss’ trial-and-error based approach continued as he jumped from “No Comment” to a first-ever solo version of “Upward.” Trying something he “learned in college,” he then played through a version of Dave Matthews’ “Pay for What You Get.” The second set saw several favorites and a few welcomed surprises, such as rare 30db tune “Susannah.” As the crowd continued to shout requests, it was obvious that “Final Word” was in high demand. Despite the fact that Bayliss couldn’t remember the words, Barry provided him with the lyrics from the screen of his smartphone and Bayliss soldiered through as the crowd verbally contributed the song’s familiar guitar riff.

Foreshadowing the band’s upcoming set with Gene Ween at Summer Camp, Bayliss introduced a new cover of Ween’s “Baby Bitch,” followed by Beck’s “Debra.” He ended his first set with the infamous “2 Dips” before returning for a grand finale consisting of 30db’s “Liar” and “Hajimemashite.” Whether using the solo show as a warmup for festival season or attending for an impromptu Illinois Umphrey’s Crew reunion, fans packed into the small Chicago bar left with something – or a few things – to brag to their friends about.