A pioneer of the underground comix movement as well as a noted rock poster designer, artist Greg Irons was among the counterculture's truly singular voices. Born September 29, 1947, and raised in suburban Philadelphia, he drew obsessively throughout childhood, influenced primarily by N.C. Wyeth and Heinrich Kley; by the time he arrived in San Francisco in early 1967 he was not only an accomplished artist but also a self-taught musician and experienced acid tripper who'd begun dabbling in LSD almost as soon as the drug hit the East Coast. Upon arriving in the Haight-Ashbury district he wandered around sketching everything in sight, these acid-enhanced drawings later providing the rough material for his concert poster designs.

Irons' first commissioned poster celebrated the grand opening of the Western Front dancehall; he met with Fillmore West promoter Bill Graham soon after, gobbling speed to complete his first work for the venue by the next day as per Graham's request. Lacking the grasp of color common to many of his contemporaries, Irons instead distinguished himself through his unique linework as well as his nuanced sense of texture and balance; the eight posters he produced for the Fillmore between 1967 and 1969, among them pieces promoting appearances by Chuck Berry, Santana, and Moby Grape, also exhibit a cartoon-like exuberance well attuned to the joyful spirit of the times. He additionally worked as a tracer on the Beatles film #Yellow Submarine.

Irons soon moved into underground comix, with his work appearing in titles including Skull Comics, Slow Death Funnies, The Legion of Charlies, Auto Be Recycled, Knockabout, Rovi