[10] In 1908, Imbrie opened a law practice in Baltimore with Howard McCormick, who later served as a long-time professor of English at the United States Naval Academy.

His guide to Africa was Richard Lynch Garner, who had been assigned by William Temple Hornaday, the director of the New York Zoological Society, to bring back a live gorilla, which he did.

[12] In late 1915 Imbrie enrolled as a volunteer driver in the American Ambulance Field Service, which was part of the Automobile Section of the French Army.

[15] With the Treaty of Brest-Litovsk about to be signed, ending the war between Germany and Russia, the American legation moved north in late February, 1918.

In April Ambassador David Francis sent Imbrie back to Petrograd, where he stayed for five months as the primary and at times the sole U.S. representative in the city.

[19] Imbrie was next posted to Crimea, where the southern division of the White Army was active; however, when he arrived in Turkey in December, 1920, he found it, too, had collapsed.

There he met Katherine Helene Gillespie (1883–1968), an American relief worker caring for Armenian and Greek orphans of genocide and war.

[21] Imbrie continued his reconnaissance work, befriended Mustapha Kemal, the new president of Turkey, and tracked American commercial interests in the area.

[23] Imbrie’s next post was to Tabriz, Persia (Iran); however, before assuming that duty, he was temporarily reassigned to Tehran when Consul Bernard Gotlieb went on leave.

[24] Imbrie immediately immersed himself in this new post as Persia struggled with both internal strife, involving politics and religion, and external pressures, including oil interests and foreign entanglements.

On the morning of 18 July, Imbrie went to visit a well in the city's bazaar where it was alleged a man had lost his sight because of a sacrilege but had had it restored when he repented.

[29] Imbrie's body was shipped home aboard the USS Trenton (CL-11), the first U.S. warship to enter the Persian Gulf,[30][31] arriving in the United States on September 27, 1924.

According to Major Sherman Miles, a United States Army General Staff officer sent to Tehran to investigate, the murder was deliberate.