Inspired by H. G. Wells' classic The Island of Dr. Moreau, Shepherd tells the tale from the perspective of Moreau’s 16-year-old daughter, Juliet. Abandoned by her father, she lives in poverty in Victorian-era London and tries not to think about his scandalous experiments which caused her ruin. When she learns he is alive and working on a remote island, Juliet is determined to confront him. Accompanied by Montgomery, her father's handsome young assistant and Edward Prince, a rugged castaway, Juliet discovers that her father has experimented on animals so that they resemble and behave as humans. Horrified, she knows she must stop him before it’s too late and the island falls into chaos.