ninme found this
excellent account of the escape of 6 Americans from the Iranian embassy back in 1979. A CIA agent named Tony Mendez got the word a few weeks after the capture of our embassy that some staff had escaped and were in hiding in Teheran.
his strategy was straightforward: The Americans would take on false identities, walk right out through Mehrabad Airport, and board a plane. Of course, for this plan to work, someone would have to sneak into Iran, connect with the escapees, equip them with their false identities, and lead them to safety past the increasingly treacherous Iranian security apparatus. And that someone was him.
The big hitch in the plan was thinking of some reason "Canadians" would be in Teheran in the first place. All the usual suspects --journalists, diplomats, oil men-- were well known to authorities.
Then Mendez hit upon an unusual but strangely credible plan: He'd become Kevin Costa Harkins, an Irish film producer leading his preproduction crew through Iran to do some location scouting for a big-budget Hollywood epic.
And there begins the wonderful tale.