WARNING: The following contains spoilers for Season 2, Episode 2 of Dr. Stone, streaming now on Crunchyroll.

Anything is possible in Dr. Stone's future stone age, especially when you have Senku Ishigami to show you how. The long-anticipated first phone call of the new stone age was as heartwarming as it was innovative. However, Senku's most impressive technological advancement could bring trouble along with it.

At the end of Season 1, Senku and the Kingdom of Science constructed two cell phones to be their secret weapon during the war against Tsukasa's empire. The Kingdom's goal during this episode was to get the second cell phone to Taiju and Yuzuriha, Senku's friends who haven't been seen since the beginning of the first season. They've been inside the empire waiting for Senku to make his move after "faking" his death.

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It wasn't easy to get the device to its destination. Homura, the spy for the empire, stood in their way. Chrome, Magma and Gen moved to transport the second cell phone, and the rest of the village tried to distract and ambush Homura. It didn’t go well for them, and the informant realized she needed to track down the transportation team. But of course, Senku had a way to track Homura. What happened next was a full display of the cell phone’s power. Senku and Gen used morse code to communicate and formulate a successful pincer attack against Homura. What was once a formidable foe and pillar of Tsukasa’s might was conquered by successful communication.

Chrome, Gen and Magma then get the phone to Senku’s gravesite and bury it for Taiju and Yuzuriha to find, but there was one small hiccup. As they’re entering Tsukasa’s domain, Gen warns them that there’s a person in the army with amazingly good hearing. While digging a hole for the phone, a loud bang echoes through the empire. The sound is picked up by an unnamed character in yellow armed with a bow and arrow. The transportation crew manages to finish their assignment. For the time being, it does not seem like they were discovered, but they sure cut it close.

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This mysterious figure seems incredibly skilled. An archer with magnificent hearing could be the one thing to sour Senku’s plan, especially since it all relies on coordinated communication. If the archer overhears a conversation on the cell phone, Tsukasa would have the upper hand. In fact, if the archer even sees the communication device, it all but ensures a defeat for Senku.

Senku’s plan also depends on no one in the empire caring about his gravesite. It’s a beacon for Taiju and Yuzuriha, but meaningless to the members of Tsukasa’s army. No one would go there often enough to see his friends retrieve the cell phone and communicate with him. The archer, however, is at the very least suspicious of the area now. There’s a reason for the archer to continue to observe the area.

As the episode closes, Senku awaits a phone call, and there’s no doubt in his mind who it’ll be from. In a scene that would make Alexander Graham Bell shed a tear, the phone finally rings and it’s none other than Taiju on the other side. It’s an incredible and emotional moment as these best friends haven’t heard from each other since near the beginning of the series. The phone is fully functional, and at least right now, it would seem The Kingdom of Science has the advantage in the war.

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