"Weakness…!!" (弱点…!!, Jakuten…!!, Viz: Achilles' Heel…!!) is chapter 361 of the original Naruto manga.
With Sasuke immobilised in clay, Deidara traps him in a sphere of C4 bombs. Sasuke manages to escape but quickly starts to disintegrate. This is, once again, a genjutsu, and the real Sasuke attacks Deidara. Sasuke explains that he earlier discovered that lightning neutralises Deidara's explosives. By using Chidori on himself, he removed the threat the microscopic bombs he inhaled posed. Sasuke owes his survival to the Sharingan.