“Identity Crisis” from The Batman Chronicles #17 (June 1999), written by Chris Renaud (director of Despicable Me and The Lorax), art by Graham Nolan and Bill Sienkiewicz.
--Bill Sienkiewicz' variant cover for Batman: City of Madness (2023)
Poison Ivy by Bill Sienkiewicz
Source: comicartfans.com
TWO-FACE in "Identity Crisis"
During the lawless era of No Man's Land, a once-prominent psychiatrist learns the secret of Batman's secret identity and decides to sell it to his former patient: Harvey Dent.
By Chris Renaud (director of Despicable Me and The Lorax), Graham Nolan, and Bill Sienkiewicz, originally published in The Batman Chronicles #17 (1999).
Batman, Green Arrow, and the Question by Denys Cowan and Bill Sienkiewicz, painted for the Fables crossover (no relation to the Vertigo series). Info about the crossover, plus Cowan's original pen-and-ink version, can be found over here at TheBatSquad.net.
Batman villain portraits by Bill Sienkiewicz (Or: "When bad CGI happens to good artists")
Seriously, that's like the Nod Flenders version of Anarky.
Source: about-faces.livejournal.com
The Joker by Bill Sienkiewicz.