The Defenders #54

The cover of this December 1977 issue — titled "Dark Waters, Swift Doom!" — plunges the Defenders into a churning underwater battle, with the Hulk, Sub-Mariner, and two female teammates surging upward through a torrent of bubbles while massive red robotic arms close in from every side and a mysterious purple-hued figure looms at the right. The inset corner box teases the broader roster, and the cover copy warns that something funny happened on the way to the U.S.S.R. — though the Defenders may not live to laugh about it. George Pérez's pencils, inked by Ernie Chan, give the whole scene a wonderfully kinetic energy that makes this one of the more visually compelling entries in the series' run.