When Adams arrives, he discovers the English are already building warships for the South, and realizes that the very fate of his country is at risk. He enters into a high-stakes game of espionage and diplomacy, determined to save the nation his father and grandfather built.

Adams' son, Henry, accompanies his father on the mission, knowing the impact it will have on the war if they fail. While in London, Henry renews a friendship with Baxter Sams, a Southerner. Baxter is studying medicine at the Royal College and has fallen in love with an Englishwoman whose family disapproves of Americans. He is torn between reviling slavery and running medicine across the blockade to help his Confederate brothers. The two young men give voice to the debate raging between thousands of friends and families at home and abroad-and between Charles Francis Adams and the British government.

In the Lion's Den is an epic tale of intrigue, loyalty, and courage set in London and New York at a time when the British Empire was at its zenith and the American nation in collapse. Casting light into a little-known aspect of history, Elizabeth Cobbs Hoffman delivers a gripping narrative of one of America's finest politicians.