She laughed again with a sort of fierce satisfaction.  “You have done something more than that.  You have given me just the power I needed to help you.”  She came up and with a quick impulsive gesture laid her two hands on my arm.  “Neil, Neil, my lover!  In a few hours from now you can have everything you want in the world.  Everything, Neil—­money, freedom, love—­” She broke off, panting slightly with her own vehemence, and then drawing my face down to hers, kissed me again on the lips.

I suppose I ought to have felt rather ashamed of myself, but I think I was too interested in what she was going to say to worry much about anything else.

“Tell me, Sonia,” I said.  “What am I to do?  Can I trust your father and McMurtrie?”

She let go my arm, and stepping back sat down on the edge of the small table which I had been using as a writing-desk.

“Trust them!” she repeated half scornfully.  “Yes, you can trust them if you want to go on being cheated and robbed.  Can’t you see—­can’t you guess the way they have been lying to you?”

“Of course I can,” I said coolly; “but when one’s between the Devil and Dartmoor, I prefer the Devil every time.  I don’t enjoy being cheated, but it’s much more pleasant than being starved or flogged.”

She leaned forward, holding the edge of the table with her hands.  “There’s no need for either.  As I’ve told you, in a few hours from now we can be away from England with money enough to last us for our lives.  Do you know what your invention is worth?  Do you know what use they mean to make of it?”

“I imagine they hope to sell it,” I answered.  “It wouldn’t be difficult to find a customer.”

“Difficult!” She lowered her voice to a quick eager whisper.  “They have got a customer.  The best customer in Europe.  A customer that will pay anything in the world for such a secret as yours.”

I gazed at her with a carefully assumed expression of amazement and dawning intelligence.

“Good Lord, Sonia!” I said slowly; “do you mean—?”

She made an impatient movement with her hands.  “Listen!  I am going to tell you everything.  What’s the good of you and I beating about the bush?” She paused.  “We are spies,” she said quite simply, “professional spies.  Of course it sounds absurd and impossible to you—­an Englishman—­but all the same it’s the truth.  You don’t know what sort of man Dr. McMurtrie is.”

“I appear to be learning,” I observed.

“He has been a friend of my father’s for years.  They were in Russia together at one time—­and then Paris, Vienna—­oh, everywhere.  It has always been the same; in each country they have found out things that other Governments have been willing to pay for.  At least, the doctor has.  The rest of us, my father, myself, Hoffman”—­she shrugged her shoulders—­“we are his puppets, his tools.  Everything we have done has been planned and arranged by him.”