The Assassin's Creed games have thrived on stealthiness and effective weaponry. The lead character has sported a hidden blade in every installment of the series. The spring-loaded knife attaches under the forearm with a leather brace and pops out to wreak quiet havoc on demand.
Master armorer Tony Swatton, the focus of the Man at Arms YouTube series, has created a real-world design based on a licensed toy version of the hidden blade. He started by reverse-engineering the toy to determine the size and how the retracting mechanism works.
The actual blade is made from steel cable, a fascinating process that turns the rope-like metal into a sharp, dangerous-looking blade. The biggest challenge was crafting a spring mechanism that wouldn't just send the blade shooting out like a ballistic weapon.
For good measure, Swatton also forged a pirate cutlass from Assassin's Creed 4, noting the likeness to a blade he crafted for the Elizabeth Swann character in "Pirates of the Caribbean: Dead Man's Chest."
Both items got a good workout, proving their mettle against some unsuspecting watermelons and unopened drink cans.
The hidden arm blade has long been a staple of historical fiction stories, but the real version seems like it would be surprisingly effective. Keep that in mind should you end up time-traveling back to the Third Crusade and finding gainful employment as a stealth killer.