Tales of Suspense #59 sets up the first major challenge to Tony's secret identity: his heart condition is getting worse, and the chest plate can longer provide the support he needs. Consequently, he collapses in front of Pepper and Happy -- and that's when all hell breaks lose.

Upon seeing their boss and friend in distress, Pepper and Happy react like rational, compassionate human beings and insist on calling a doctor. But Tony's thinking, "No! If a doctor sees what I've got under my shirt, he might guess who I really am!" Thus, he refuses help and slips away -- which makes him look like an absolute lunatic. Poor Tony.

When Tony puts on his Iron Man armor to tussle with the Black Knight, a recharge allows him to recover. But, of course, Pepper and Happy don't know that. As far as they know, Tony is dying alone in his office. So they try to break down the door -- only to discover that it's reinforced with solid steel plates. Hmm. Odd.

As the battle with the Black Knight continues, Happy - ever determined - decides his next plan of attack is to break in through Tony's window. Unfortunately, the Black Knight sees him and snags him as a hostage, forcing Tony to come to Happy's rescue.

Obviously, Tony is ultimately able to subdue his opponent. But when he returns to his office, he comes to a terrible realization:

He's now trapped! Without the power that the full suit of armor supplies, he can't keep his heart beating. Oh crap! This is quite a pickle!

Tragically, Tony faces the prospect of being in even less control of his own life. Even worse, he also has to explain to his employees what happened to their boss. And as we all know by now, Tony sucks at coming up with good excuses, which just leaves everyone confused and suspicious. Oh dear. What will Tony do? 

That, gentle readers, is the plot of the next few issues.