It might seem odd to find it in a theater instead of a smoky bar, but the Denver Center Theatre Company's It Ain't Nothin' but the Blues is a scintillating piece of work.

The songs have been carefully chosen to illustrate the history of the blues with all its hot permutations, from jazz to rock to country and beyond. But the mother of them all is African music, and the show opens with a traditional African song ("Odun De") before moving on to traditional tunes from slavery days ("Blood Done Sign My Name") and weaving in folk music from working-class English and Irish immigrants ("My Home's Across the Blue Ridge Mountains"), French Cajuns ("Goin' to Louisianne") and others. The first act alone contains 26 songs; their progression reveals the connections between African-American music and African-American-impelled music, as white folks such as Hank Williams and Janis Joplin interpreted it.

The second act takes on the great black migration of the Forties, when 5 million Southern workers packed up and moved to Chicago, where factory work offered some relief from grinding poverty. The blues took on a new, funkier life in the city. Fabulous songs like "The Thrill Is Gone," "I Put a Spell on You" and "Hoochie Coochie Man" send shivers up the spine with their authority.

The subject of so many of these songs is powerful emotion and the driving causes behind that emotion: meaningless and grinding work, hopeless poverty, loss, despair, desire, anguish and resignation, defiance, hate, anger, cynicism, love and hope. The show's artful history lesson never loses speed over trifles--it moves quickly from one theme to another, showing rather than explaining the various forces at work in the music. Director Randall Myler and singer/songwriter Ron Taylor conceived this project together, and they waste little time on anything but the music. The sets are appropriately simple--a night-sky backdrop and a country fence grace the first act, a cityscape the second. All of the energy comes from the singers.

Eloise Laws is all elegant simplicity and pure, luscious feeling, sometimes earthy and sometimes ethereally spiritual--you could listen to her sing all night. Lita Gathers's powerful voice rocks the roof above your head with its spontaneous flights across the scales. Laura Theodore, who last year sang Janis Joplin's role in the DCTC's Love Janis, is back with more of the same, and she's terrific--but I still wanted to hear more from Laws.

The men are equally good. Taylor's dynamo performance in numbers like "Born Under a Bad Sign" lends both sardonic humor and grand pathos. Dan Wheetman does the white-guy music with all the tantalizing feeling of the originals he imitates. Chic Street Man's masterful funkiness lights up the night with his cool. And "Mississippi" Charles Bevel's rich, mature voice and expertise provide the true soul of the whole show.

It's difficult to find enough adjectives to praise this evening of great music and honest performances. In the end, It Ain't Nothin' but the Blues provides an unanticipated but mighty reminder that human magnificence lies in the creative response to the demands life makes and the sufferings it poses.