transparent
Explanation
The comic depicts a classic supervillain scheme gone wrong. In the first panel, a bald villain in what appears to be a lab or lair announces his creation: "I've done it! A substance which no steel can slash, no gun can pierce, but is completely transparent to light!" -- essentially an invisible, indestructible material.
In the second panel, someone asks, "But why? Whatever for?" The villain explains with sinister glee: "Fifty years ago, humans killed whatever and whenever and however they wished." He continues: "Now? Now they will cry out for food, water, air..." The third panel shows people trapped behind an invisible barrier, calling out for help, with a "Henchman" character standing nearby. The final caption reads: "And no one will believe them."
The humor lies in the darkly creative evil of the plan. The villain has essentially created invisible, indestructible walls to trap people. Because the material is transparent, no one on the outside can see the barrier, so when the trapped victims cry out for help, onlookers will see nothing confining them and assume they are simply acting strangely or are mentally unwell. It is a diabolical twist on the concept of an invisible prison -- the real cruelty is not just the confinement but the fact that nobody will believe the victims are actually trapped. The comic plays with the supervillain trope of overly elaborate, almost Rube Goldberg-like evil plans, and finds dark comedy in the idea that the most terrifying prison is one that nobody else can perceive.