"Night Shift"
Trapped in the sewers of Los Angeles, and taking a dunking from some mis-shapen savages; Captain America has seen better days. The mutated and mentally-challenged test rejects continue to attack relentlessly.
Doctor Karl Malus sees his chance to escape Cap's custody. He runs down a blind tunnel and smack bang into a Werewolf. Bad break.
The battle's not likely to end soon as the mutates appear indefatigable. Cap immerses himself under the sewage water, willingly this time, hoping to bypass the inhuman horde. As he re-surfaces, Cap is confused to be blocked off by more mutates.
A motley group of characters with bizarre powers, calling themselves "Night Shift" appear in the tunnel and start mopping up the mess of mutates.
Cap also comes face-to-snout with the Werewolf, but years of battle-honed reflexes are more than a match for uncoordinated ferocity.
The leader of the strange crew is the enigmatic Shroud, Master of Darkness. Shroud's ploy is to pretend to be a criminal, that he may easier infiltrate the underworld. To maintain his cover, the Shroud envelops Cap in a veil of darkness.
Cap and the Shroud agree on a ruse to hoodwink the rest of the supernatural team. Cap has to go along with the Night Shift to the Power Broker's base. Their interest is to stop the flow of new mutates into the sewer system and Cap wants to find his friend, D-Man.
Bingo on both counts. Curtiss Jackson, once head of the West Coast Corporation is revealed as the Power Broker. He has a private shuttle tunnel under the house, which he leads Captain America to the labs where Augment experiments have been conducted.
D-Man and a costumed woman (the second Ms. Marvel) are manacled upright with intravenous feeds attached to both of them. D-Man bursts free and lurches at Cap, not seeming to recognize his associate. D-Man, now as mindless as the sewer mutates, continues to lunge at Cap until he collapses exhausted, apparently suffering heart failure.