mustafa alani was briefed by the head of counterterrorism.oyal al qaeda had already tried to kill. he told him what happened next. a very lucky break. saudi intelligence gets a tip. an informant tells them about the plot. but it's too late to stop the bombs taking off on passenger jets. >> by that time, the shipment's already left the country. >> all that the saudis know is that the bombs are headed to the u.s. then more luck. two packages were addressed to medieval crusaders, a saudi blunder that leads them to the tracking numbers. saudi muhammad bin nayef calls the white house, which goes into crisis response mode. >> they never questioned the credibility of the information. >> british intelligence is alerted too. but authorities still can't locate the deadly cargo. >> so it was a very complicated to find out what the shipment is moving, where it is now. >> many hours and several flights later, one passenger is located in dubai. the other at east midland's airport in britain. police arrive and search for the explosive. the police bomb squad