As much as I felt Jack Kirby veered off course in his treatment of the Captain America book when he assumed creative control of the title upon his return to Marvel in 1976--as well as radically altering the characterization of its principal characters--I found myself nevertheless admiring his turnaround on Sharon Carter, Steve Rogers' girlfriend and former agent of S.H.I.E.L.D., whom Kirby at first had pigeon-holed into a civilian woman who moped on the sidelines about her super-hero boyfriend's responsibilities not allowing the two of them to lead a normal life, to the point of becoming something of a shrew on the matter.
But that all changes when Cap is later abducted and Sharon is sidelined by exposure to the tranquilizer gas used to take him. The SHIELD regional director, stalled in the Arnim Zola matter, decides to bring Sharon back into harness as an agent to crack the case--and Kirby's treatment of former Agent 13 gives Sharon Carter responsibilities of her own. And woe be to whoever she's gunning for, because...
...you don't mess with an agent who's going into action sporting a new coiffure.
All kidding aside, it's a nice effort on Kirby's part that serves to tell us that Sharon has shaken off her funk and returned to active duty in a profession she excels at. And when she's ready to work--brother, she's ready to work.
(Sometimes I'm torn between cringing at Kirby's misuse of emphasis, or just going with it.)
As we'll see further evidence of, Kirby's characterization of Sharon Carter falls somewhere inbetween Stan Lee's capable yet inescapably feminine and vulnerable agent and Steve Englehart's cocky and battle-savvy agent. It's a pleasure here to see Sharon act alone and independently, resolute and confident that she'll accomplish her task; and while Lee had her in a similar role as Irma Kruhl, her decisions here are made with self-confidence and aren't tempered with either worry or misgivings.
But even such a capable SHIELD agent can be surprised by the unexpected--and the financier SHIELD suspects of bankrolling the horrors within "File 116" will test Sharon's readiness to handle her mission, with Kirby's choice of adversary for Sharon to encounter nicely raising the tension level of the scenes which follow.
With the Red Skull's ties to Zola, of course, Kirby has found a way to link Sharon's mission with Cap's situation as Zola's prisoner. Fortunately, Kirby's plans for Sharon don't include something as trite as her capture by the Skull; on the contrary, what happens next adds to her character significantly, as she uncovers the shocking true identity of Cyrus Fenton.
"...I'd advise you to cooperate during this inquiry." You can never underestimate the Red Skull, of course, but even he has to have a healthy respect for Sharon at this moment. That said, the Skull has smoothly regained the upper hand in this meeting with his mention of Cap, and a veiled threat which indicates his life is in danger. Sharon may still be in the driver's seat--but the Skull has put himself in the position of choosing the direction they follow from this point.
What follows during the trip to Castle Zola is a game of cat and mouse played by the Skull, who, despite Sharon's position of strength, gives the impression that it's his wishes that are being indulged. Whether Sharon is playing along, or dropping her guard due to her worries about Cap, remains to be seen--but the Skull's tightly-contained villainy practically radiates from these panels.
By the time they arrive, Cap and his fellow captive, Donna Maria, have escaped Zola's custody and reached the castle courtyard; but the castle is on the verge of self-destruction, and Cap's vision has been severely impaired by an attack from one of Zola's creatures. The Skull, by contrast, seems to think he holds all the cards, though Sharon is quick to remind him that he's still very much in her custody. Yet Kirby demonstrates his knowledge of the Skull's character by having the villain contemptuously test those boundaries.
Before the situation explodes, the castle finally meets its end, separating Cap and the Skull from the others and giving the Skull the opportunity to take advantage of Cap's blindness in a final battle amidst the chaos of the ongoing destruction around them--destruction which swiftly engulfs the Skull before he can bring about Cap's death. But the fierce explosions continue, with Cap injured in the process--and we learn that Sharon hasn't been as cooperative with the Skull as she let on.
It's the last we'd see of Sharon Carter on Kirby's watch, with the artist scheduled to once again tender his resignation to Marvel and depart following two remaining issues of Captain America. The abrupt end of Sharon's appearance in the book at this point is curious, given that the SHIELD installation that Cap is taken to for his recovery falls under attack from the Night Flyer, and Sharon would have fit right in with the defense forces--nor would she have likely been anywhere else, with Cap on the injured list. Be that as it may, Kirby has featured her well in this ongoing saga with Zola and the Skull, a parting gift to the character which was better late than never.