I Spy — Natalie Sumner Lincoln

Natalie Sumner Lincoln (1881-1935) was the author of The Trevor Case (1912), The Lost Despatch (1913), The Man Inside (1914), COD (1915), I Spy (1916), The Nameless Man (1917), The Moving Finger (1918), The Three Strings (1918), The Red Seal (1920), The Official Chaperon (1920), The Unseen Ear (1921), The Cat's Paw (1922), The Meredith Mystery (1923), The Thirteenth Letter (1924), The Missing Initial (1925), The Blue Car Mystery (1926), PPC (1927), The Secret of Mohawk Pond (1928), The Fifth Latchkey (1929), Marked 'Cancelled' (1930), and Thirteen Thirteenth Street (1932).