In February of this year, Kim Jong-un’s estranged half-brother Kim Jong-nam was ambushed in a Malaysian airport by two women bearing VX — a lethal chemical weapon 10 times more powerful than sarin. He died en route to the hospital. Subscribe on YouTube: bit.ly/1BycsJW As his assailants, Siti Aisyah and Doan Thi Huong, go on trial, a new documentary explores whether Kim Jong-nam's half-brother -- North Korean leader Kim Jong-un -- ordered the hit. In this excerpt from "North Korea's Deadly Dictator," learn about Aisyah and Huong’s deadly surprise attack on Kim Jong-un’s half-brother — and what it may reveal about the North Korean leader and his regime. Watch "North Korea's Deadly Dictator" Wed., Oct. 4 on PBS and online: www.pbs.org/wgbh/frontline/film/north-koreas-deadly-dictator/ Facebook: www.facebook.com/frontline Twitter: twitter.com/frontlinepbs Google+: plus.google.com/+frontline/posts FRONTLINE is streaming more than 200 documentaries online, for free, here: to.pbs.org/hxRvQP FRONTLINE is made possible by PBS and CPB. Major support is provided by The John D. and Catherine T. MacArthur Foundation. Additional support is provided by the Ford Foundation, the Park Foundation, The John and Helen Glessner Family Trust, the Heising-Simons Foundation, Wyncote Foundation, and the FRONTLINE Journalism Fund with major support from Jon and Jo Ann Hagler on behalf of the Jon L. Hagler Foundation.