This story takes place in Zalamar, "somewhere in Arabia." But when April Dancer, disguised as Sheikh Ali Hassen's daughter Fatima, speaks English, nobody is surprised. Indeed, it seems everyone in Zalamar speaks English instead of an Arabic language.
In the desert, Mark Slate has been captured by 4 enemy guards. His hands are tied. Via communicator, he asks April to create a diversion, which she does by starting a large oil fire. Mark waits for about a minute until April comes over to untie his hands, before running away -- but his feet were never tied, he could have run away immediately.