After successfully seeking out the ultimate slider in the 2004 stoner comedy Harold and Kumar Go to White Castle, the cannabis-craving twosome returns in this high-flying sequel that finds them labeled terrorists for attempting to sneak a marijuana-smoking implement on a flight to Amsterdam. Harold (John Cho) and Kumar (Kal Penn) have just finished gorging themselves on savory White Castle hamburgers when they return to their apartment and hatch a plan for Harold to win the heart of his crush, Maria (Paula Garcés). Maria is going to Amsterdam, and if Harold can catch up with her overseas perhaps he can strike up a real love connection. After a close call with airport personnel and a chance encounter with Kumar's ex-girlfriend Vanessa (Danneel Harris) -- who hadn't yet told Kumar that she's engaged to be married -- the pot-loving pals finally board their flight for Amsterdam. Unfortunately for Harold, Kumar isn't able to endure the lengthy flight without an innocent puff or two from his smokeless bong. When the plane hits some turbulence and the bong is mistaken for a bomb, the flight is diverted to Guantanamo Bay and our spliff-smoking heroes are detained by overzealous Deputy Chief of Homeland Security Ron Fox (Rob Corddry). Now, if they can just escape from the world's most notorious prison compound, perhaps this hapless duo can succeed in convincing the authorities that they aren't enemy combatants, and that Kumar made the mistake of his life by letting Vanessa go. But before they can prove their innocence and get the girls, Harold and Kumar will have to outsmart the dreaded Ku Klux Klan, contend with a particularly precocious Cyclops baby, and successfully elude everyone's favorite debauched former child star -- Neil Patrick Harris.