Viewers may have been prepared for a changed -- and, it turns out, bearded -- Barry Allen when The Flash returns next month for its fourth season, but they probably weren't expecting him to be confronted by a relatively obscure threat from the Scarlet Speedster's comic book past: the Samuroid.

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Teased in July in the Comic-Con International sizzle reel, the villain at last stepped out of the shadows in the new television promo for Season 4, leaving fans to wonder, Wait, what the hell is a Samuroid?

As the name suggests, it's a robot samurai, part of an army of mechanical warriors constructed by the Japanese criminal Baron Katana to wage war against the country's foreign "benefactors" and usher in a new "Age of the Samurai." Introduced, along with their creator, in 1968 in The Flash #180, the Samuroids are described as "virtually indestructible," although of course they can be (and ultimately are) destroyed. Still, they are formidable opponents, equipped with jetpacks, nearly impenetrable armor, electrified swords and, in some instances, flaming arrows.

In the two-part story, by writer Frank Robbins and artists Ross Andru and Mike Esposito, Barry Allen and Iris West arrive on vacation in Japan, where Barry is tasked with passing along a warning to the local Interpol office about Katana. He immediately becomes involved in the "autopsy" of a robot samurai discovered by fisherman, which naturally places The Flash on a collision course with Katana and his army. With help from Iris and his friends from Interpol, The Flash ultimately defeats the Samuroids, and Katana apparently leaps to his death rather than suffer the disgrace of capture.

Samuroids, from The Flash #180

And that was the last anyone ever saw of the Samuroids, at least until 2008.

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In The Brave and the Bold #13, by writer Mark Waid and artist Jerry Ordway, The Penguin acquires "dusty old Samuroids" developed years earlier by T.O. Morrow and forgotten about in a warehouse. "I designed them years ago for a low-paying warlord named Black Talon," Morrow says when called upon to appraise the contents of the building, given to The Penguin by The Riddler as payment for a debt. "In retrospect, they seem as crude and overreaching as he was." Although the two stories take place in different continuities (long before and long after Crisis on Infinite Earths), the mention of Black Talon is likely no coincidence, as Baron Katana's ancestral home was called the Black Heron.

Samuroids, from The Brave and the Bold #13

With a quick upgrade by Morrow, the Samuroids become key to Oswald Cobblepot's scheme to become "first in the global security business" by selling units to the highest bidders in the Middle East. But first, he decides, he'll use the Samuroids to eliminate Bruce Wayne, who's not only attempted to block his "immoral" business enterprises but has also proved frustratingly resistant to assassination. That of course brings the killer robots into conflict not only with Batman but with Jay Garrick, who just happens to be visiting Wayne Manor at the time of their attack.

Samuroids, from Batman #21

The Samuroids crop up one more time, in DC's current Rebirth continuity, no less, in April's Batman #21. It's a blink-and-you'll-miss-it moment (a single panel), easily overlooked amid the story-driving mysteries of the blood-spattered smiley-face button discovered in the Batcave, and the sudden appearance by the Reverse-Flash.

In the issue, by writer Tom King and artist Jason Fabok, Batman contacts a distracted Flash, who explains, "I'm kind of in the middle of a kind of Samuroid invasion thing," and that's that. It's little more than a fun callback to a nearly 50-year-old story that, oddly enough, presages the Season 4 premiere of The Flash.

From the teasers, we know on The CW drama that there will be at least one Samuroid, with a powerful sword, the ability to either fly or jump great distances, and a goal to take on The Flash. However, whether Baron Katana is at the controls remains to be seen.


Returning Tuesday, Oct. 10, at 8 p.m. ET/PT on The CW, The Flash stars Grant Gustin, Candice Patton, Jesse L. Martin, Tom Cavanagh, Carlos Valdes, Danielle Panabaker and Keiynan Lonsdale.