Two decades ago, an all-star assembly of Chicago improvisers started a new band, drawing its name from an 1841 book by Charles Mackay: Extraordinary Popular Delusions. With weekly gigs at a spot in Chicago called Hotti Biscotti, Jim Baker, Mars Williams, Brian Sandstrom, and Steve Hunt honed their sound, which could be ferocious or nerdy or diffuse, as they moment required. After a couple years, the quartet moved to a regular Monday session at Beat Kitchen, where they were resident band for more than fifteen years. Williams was from time to time called away on tour, frequently enough that the band invited another horn player, the venerable Edward Wilkerson Jr., to substitute. This inevitably led to quintet convenings with both Williams and Wilkerson, the likes of which are now legend. Without question, although they have only released two previous records, EPD is one of the signal ensembles of Chicago creative music. Mars Williams (1955-2023) had been diagnosed with late-stage cancer when EPD booked a concert at Elastic Arts Foundation at the end of August, 2023. Williams, who lived less than three months more, was on the bill. Nobody expected him to play the way he did. More than an honorary appearance, this was Mars at the top of his game, playing, as it were, for his life. With Sandstrom switching between bass, trumpet, and electric guitar, Wilkerson doubling on saxophone and clarinet as well as oud and didgeridoo, Baker on ARP synthesizer and piano as well as violin, and Hunt on all sorts of percussion, Williams' table of toys and his blazing soprano, alto, and tenor saxophones were in perfect company -- a band that could freely improvise open structures and instantly compose unforeseen suites, while maintaining a level of intensity and intrigue on par with the saxophonist's mastery. Long term relationships extending outside this group, including those with NRG Ensemble, Mars Williams' Ayler Xmas projects, as well as a variety of ad hoc and shorter-lived amalgamations, made this one of the most fertile environments for these players, and this final quintet bore the marks of a classic concert. Which it was. Fortunately, Dave Zuchowski was there to brilliantly document it in all its two-set glory. Corbett vs. Dempsey is pleased to present the entire concert on two CDs, as the fourth installment of CvsD's Mars Archive series, with a cover painting by Timothy Howe.