Twenty-five years in New Orleans' music scene makes for a mess of crossed paths, entwined bands and gutter allies. Dave Rosser had all that cinched before he got tangled up in Greg Dulli's never-ending loop, a Gordian knot of Crescent City associations that threads from Daniel Lanois' famed Kingsway Studios (where the Afghan Whigs recorded 1965 in the late 1990s) through an apartment recording space one block down Esplanade Avenue, in which producer Mike Napolitano strung Rosser's guitar over the frets of Dulli's Twilight Singers, beginning an inseparable connection that continued into The Gutter Twins and, eventually, the Whigs' 2014 comeback, Do to the Beast. In late October, the band announced that Rosser had been diagnosed with inoperable colon cancer and opened a GoFundMe account (www.gofundme.com/daverosser) that blew past its $20,000 goal in the first 24 hours. (It has since raised more than $50,000 from nearly 700 donors.) This show is the first of three benefit performances (here and in Los Angeles) in physical, spiritual and monetary support of Rosser, with reinforcements provided by Mark Lanegan, Ani DiFranco, Morning 40 Federation, King James & the Special Men, C.C. Adcock & The Lafayette Marquis and, of course, Dulli and family, who will perform the Whigs' 1996 LP Black Love in its sobering, ringing entirety. Tickets $50-$250.