Irgun knife is a fairly important object in The Chronicles of Riddick film, symbolizing Choice and Destiny. It is roughly 13" long, elaborately decorated and razor sharp. It is first seen stabbed in the back of Irgun the Strange, but is later removed by Riddick and used to strike him down. Irgun was one of the mightiest of the Necromonger soldiers, and this knife could not be removed by just anyone, so the ease at which Riddick pulls it out is rather significant. Considering the apparent connection between Riddick and this blade, there is a possibility that it is of Furyan design, hinting that Irgun was present during the Great Furyan Massacre, and a Furyan warrior stabbed him in the back and left it inside. Upon Riddick's examination of the blade, he quickly deduced that it was a half-gram heavy on the back end (This explains his unexpected miss when he threw it at the Lord Marshal). He used the knife later in the Quasi-Grotto to defend himself from Necromonger soldiers, and at that point, left it behind. It is later returned to him by the Purifier, who reveals himself to be Furyan just before walking into the VTF (Visible Thermal Front) on Crematoria. After sneaking into the Basilica, Riddick uses it in his final battle against Zhylaw "The Last", throwing it at him, but Zhylaw catches it. However, the knife cuts him slightly and is the first weapon to do so in a very long time. After Kyra injures Zhylaw, Riddick retrieves the knife, positions himself where Zhylaw escapes to from Vaako and stabs him in the head with the knife then breaks the blade off in his head, killing him.