Verb (used with object) : to unravel a situation; to unravel a mystery.    From Dictionary.com. 

Commerce, that unraveller of countries, led them to undertake this journey.    From Wordnik.com.  [Glimpses of Life and Manners in Persia] Reference

She looked round with the triumphant smile of a successful unraveller of mystery.    From Wordnik.com.  [The Toys of Peace, and other papers] Reference

Nor, before that date, was any allusion made to him, as a possible unraveller of the Sudan difficulty, in the Press.    From Wordnik.com.  [The End of General Gordon: Paras. 31-66] Reference

With nothing very spectacular to his credit, he had earned repute as a follower of long trails, and as an acute unraveller of tangled clews.    From Wordnik.com.  [The Price] Reference

Her reading had lain much among novels in which the private detective was omnipotent, the unraveller of all mysteries, the avenger of every wrong.    From Wordnik.com.  [The Golden Calf] Reference

At that time, before Rouletabille had given proof of his unique talent, Larsan was reputed as the most skilful unraveller of the most mysterious and complicated crimes.    From Wordnik.com.  [Mystère de la chambre jaune. English] Reference

Gaining the sublunary domicile of this mystical unraveller, which for the greater facility of communication with the stars he had fixed in the loftiest apartment of the house, our trio knocked at the door, which, after some hesitation, was opened by an ancient Sybil, who was presently joined by her counterpart, both "so withered and so wild in their attire," that "they looked not like inhabitants o 'th' earth, and yet were on it.".    From Wordnik.com.  [Real Life In London, Volumes I. and II. Or, The Rambles And Adventures Of Bob Tallyho, Esq., And His Cousin, The Hon. Tom Dashall, Through The Metropolis; Exhibiting A Living Picture Of Fashionable Characters, Manners, And Amusements In High And Low Life (1821)] Reference

"There came in the professional detective, Monsieur, who proves himself an unraveller of mysteries, by annihilating the very proofs he had accumulated.    From Wordnik.com.  [Mystère de la chambre jaune. English] Reference

From a fellow unraveller!.    From Wordnik.com.  [Yes] Reference

And then woman’s lot, as respects her “social promotion” in matrimony, so much sought, and so necessary for her to seek, even in spite of her conscience, and at the expense of her happiness — the unravelling of that lot would also come very natural to this expert unraveller.    From Wordnik.com.  [The Essays of "George Eliot" Complete] Reference

Of realty the rarest-veinèd unraveller; a not.    From Wordnik.com.  [Poems of Gerard Manley Hopkins Now First Published] Reference