Marvel Team-Up Vol. 1 #140

Plot

Guest-starring Spider-Man and the Black Widow. A blackout hits New York City! Is this going to be a repeat of the terrible 1977 blackout? Not if the Amazing Spider-Man can help it! However, the murder of a pawn shop owner during the power outage...brings Matt Murdock, Peter Parker, and Natasha Romanoff together to solve the case! The web-slinger and the widow join forces to catch a killer! But during the course of the investigation, the wall-crawler discovers a mammoth citadel in Central Park...and suddenly disappears! (mycomicshop.com)