WARNING: The following contains spoilers for Dr. Stone Season 2, Episode 6, "PRISON BREAK" now streaming on Crunchyroll.
Dr. Stone Season 2, Episode 6 features a magnificent display of science, but not from everyone’s favorite mad scientist Senku. It's his aide and partner in crime Chrome who steals the show by freeing himself from prison with the bare minimum for resources. And in his improbable escape, Chrome channels his inner Senku, recreating a corrosive solution with his sweat.
This episode introduces a new character named Yo Uei, a former loose cannon police officer who Tsukasa tasks with guarding the bamboo prison and setting up the surprise attack against Senku. Tsukasa knows Senku will eventually come to rescue Chrome, so Yo oversees the traps awaiting Senku’s vehicular assault rescue plan. Chrome figures that the best way to save everyone and avoid danger is to make sure he can escape on his own.
It proves to be much easier said than done. Chrome doesn't have any resources within the confines of the cave closed by bamboo fencing. On his bathroom breaks, he tries to pick up materials, but a few plants and twigs won’t do him any good. This all changes, however, when a shadowy figure rolls a battery his way in the middle of the night. It’s the cellphone battery that was confiscated when he was captured.
Chrome initially tries to blow up the gate, but the spark alerts the guards. When Yo comes over to inspect, he assumes the small fire was caused by the twigs Chrome gathered and begins to insult Chrome’s intelligence. This prompts Chrome to feign a lower level of intelligence to further Yo’s underestimation. He pretends that boiling seawater to get salt is some grand scientific discovery, and as Yo laughs about a pathetic seawater escape plan, Chrome hatches one. He remembers Senku separating saltwater with electricity to produce sodium hydroxide, a chemical powerful enough to melt faces.
From there, Chrome gets to work. He doesn’t have seawater, so he uses the next best thing: his sweat. He relentlessly exercises to fill an entire cup of sweat. With the battery, he makes the chemical and douses the ropes holding together the bamboo. As the gate crashes down, he fends off the guards and makes a run for it with Yo in pursuit. The two end at a cliff and waterfall. Yo attempts to apprehend the clever trickster only to be diverted. Chrome crushes some plants – sorrel and red shiso – to create a blood-like liquid and feign pneumonia. This diversion allows Chrome to assault Yo and escape to Ishigami Base just outside of Tsukasa’s empire.
The escape speaks volumes about Senku's impact on Chrome. It’s obvious that Chrome would not have had the knowledge necessary for his escape plan to work had not been for Senku. Still, Chrome's understanding expanding from the cool rocks and plants he collects to the fundamental comprehension behind applications of science shows his overall development. Chrome is usually confident in his abilities. When he was first introduced, Chrome felt the need to boast about his discoveries and “sorcery.” Here, he shows his work and experience instead of bragging about it. He no longer needs Senku to come up with the plan or to save him. His Houdini-esque escape calls back to his days of being the village sorcerer, although now he is a firm believer in the applications of science.
When Chrome returns to the village, he tells his legendary tale, and Senku reveals that he did get the science a bit wrong. He didn’t have a membrane, so he instead made odium hypochlorite, also known as bleach. The bleach melted the cellulose in the weeds used as rope. Regardless, Chrome’s natural curiosity finally paid off in a big way. The villagers can now regroup to enact their original plan against Tsukasa’s army, although it will be more difficult now that Tsukasa knows something is up.