The eighth annual edition of this sprawling celebration of improvisational comedy brings together performers from around the U.S. and abroad; Chicago, of course, is heavily represented. The lineup ranges from fledgling talent to returning stars who have won fame and big bucks appearing in and/or writing for movies and TV. This year’s festival, the largest and most diverse yet, is divided into several series–Mainstage, Showcase, Sketch, Solo, Duo, and Fringe–as well as an all-night improv session, a series of daytime “Lunchbreak” performances (presented in conjunction with the city’s cultural affairs department), forums, workshops, and numerous special events. ¥ The Chicago Improv Festival runs through May 1 at three principal venues: the Athenaeum Theatre, 2936 N. Southport; Theatre Building Chicago, 1225 W. Belmont; and the Playground Theater, 3209 N. Halsted. Auxiliary events take place at the Chicago Cultural Center, 78 E. Washington; Second City E.T.C., Piper’s Alley, 1608 N. Wells; ComedySportz, 2851 N. Halsted; ImprovOlympic, 3541 N. Clark; Lincoln Tap Room, 3010 N. Lincoln; and Double Door, 1572 N. Milwaukee. Tickets to shows at the Athenaeum and Theatre Building Chicago can be purchased through Ticketmaster (312-902-1500 or www.ticketmaster.com) or at the box office; tickets to events at other venues must be purchased at the box office on the day of the show. For general festival information, call 773-935-9810 or visit www.cif.com. Following is the schedule for Friday, April 22, through Thursday, April 28; a complete schedule is available online at www.chicagoreader.com.

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The headliners Beer Shark Mice, an ensemble affiliated with IO West (ImprovOlympic’s LA outpost), features Dave Koechner and Neil Flynn. Opening for them are a team of writers for SNL, including Joe Kelly, John Lutz, Jason Sudekis, and Rich Talarico. a 7:30 PM, Athenaeum Theatre main stage. $25.

CIF/Implosion College Showcase

This adult-oriented show features two local groups, Annoyance Productions’ Grabass and Pimprov. a 10:30 PM, Theatre Building Chicago. $10; 18+.

Anchorman screenwriter Adam McKay, an alumnus of Second City and ImprovOlympic, teams up with Mike Coleman, Pat Finn, Neil Flynn, Pete Hulne, Dave Koechner, Jerry Minor, and Ian Roberts to perform a classic improv form, the Armando. The evening’s guest monologuist is TV personality and Anchorman narrator Bill Kurtis. See listing for Fri 4/22 for The Saturday Night Live Writers. a 7:30 PM, Athenaeum Theatre main stage. $25.

The 4 Horsemen and Shortall and Kelly’s Show of Mystery