Downing Guinness and dunking pretzels into Cheddar Ale Dip, the packed house at Colonial Tavern peruses the laminated playlists provided by the talent. Singer Theresa Gaddy poises lithely atop a stool on stage, her only tell the bouncing right boot crossed casually over her left leg. Twisting the tuners at the head of his guitar, Jeff Leibowitz casually eyes the crowd, smiling. Finally, Gaddy shows her hand, “The way it works is, we’ll play a couple songs, and you guys should have lists in front of you. When we stop playing, just shout out what you want to hear, and we’ll write it down and definitely get to it.” Like bullets, Leibowitz is all in with Alanis Morisette’s “Hand in My Pocket,” and Gaddy calls, electrifying the audience with her clear, powerful voice.