I don't think it's a spoiler to tell you that Tim Heidecker — the Tim half of alt-comedy duo "Tim and Eric" — ends the "Tim and Eric 10th Anniversary Awesome Tour" parading across the stage wearing only black dress socks and padded flesh-toned underwear. In fact, there's not much in this madcap two-hour-and-20-minute variety show that, if revealed, could be considered a spoiler. Unless I were to reveal the nature of the intentionally overhyped unveiling of Heidecker's new character, Troi. Not to worry, I won't be describing Troi here. But what about the top-secret reveal that stretches the show into overtime (but is a highlight of the night)? The pair specifically asked the sold-out Friday night audience to "keep your claptrap shut" on that last point and made us pledge that "if it slips out of my mouth, I'm going to climb right on up to the top of Willis Tower and jump on down." If you really want to know, you can find it online. But this is Chicago, and we take secrecy seriously, so you won't read about it here. So Heidecker in his underwear is no secret. It's also a fitting image for so many aspects of this show, which is traveling the country and is appearing in Chicago at The Vic on Friday, Saturday and Monday nights (with a stop up in Michigan for two shows Sunday). Heidecker in his underwear is the comedian stripped bare. And this live show — which is ostensibly to celebrate the 10 years that have passed since the 2007 launch of the cult classic and genre-defining (if not genre-creating) television show "Tim and Eric Awesome Show, Great Job!" — is a concept stripped bare. The TV show, which ran for five seasons as part of "Adult Swim" on the Cartoon Network and has been prolifically imitated, featured bizarre characters in awkward situations with intentionally amateurish editing ratcheting up the strangeness. In a live show, there's no editing magic to deliberately cheapen up the proceedings, so the performers are left to provide the discomfort themselves (along with occasional sound effects by opener DJ Douggpound). Heidecker and partner Eric Wareheim relish this responsibility. These guys know how to take a joke and play it for a laugh, then play it for