Callum 'Cal' Jardine is a soldier of fortune.
He is not a spy, at least not when we first meet him. He never really wants to be a spy though he will find himself working for British Intelligence. He is a soldier, when the world will let him, or a trainer of soldiers when he has to be to make a living. Spying - not so much. But he is kind of good at it.
On our initial contact with Jardine, he is a smuggler or sorts, using his wide array of contacts throughout Europe to smuggle Jews out of 1935 Germany to places where they will not be so ill treated. He is performing a much needed mission of mercy for those that he is able to help and for that he should be lauded. He also charges, not exorbitantly, for these services so when someone asks if he is kind of a Robin Hood, he responds, "No, but neither am I the Sheriff of Nottingham."
One of the ways he is able to operate so well in Nazi Germany was that he was "partly raised in" that nation so he not only speaks the language like the partial native he is, he understands the people and knows in this land where the Nazis are taking such total control where there are still people less than thrilled with the Third Reich mentality.
Such is the situation when a representative from British Intelligence comes to visit with a request for his help in a matter or two. As the gentleman put it, "Certain worthy people at home require a disreputable character to do an honourable thing, and I advised them you rather fit the bill, you being a multilinguist and something of an adventurer. It also has to be a chap with certain military skills, which you also possess." True to Jardine's nature, he took the statements and the comments as neither a compliment nor an insult.
Jardine is likely in his late 30's, "still a handsome bugger ... with the build of the rugby back row he had once been, a hard man who lived a testing life, the face lean, with the scars to prove it faintly evident on brow and jaw." He is also said to have "piercing blue eyes, under those pale eyebrows and lashes" and can quickly produce his "seductive, lopsided grin". He has lots of lady friends seemingly all over the place and each one tends to treat him quite fondly but are not surprised nor heart-broken when life takes him to some other locale.
Those locales that he will visit on behalf of British Intelligence will be Abyssinia (Ethiopia) where Mussolini is trying to absorb and the British not so pleased and then back to Europe where trouble will call him to Franco's Spain and to Czechoslovakia where the Sudetenland is being absorbed by Hitler.
"Purity and poverty find it hard to coexist, especially for a widow with three children."