The characters in Mao II are Bill Gray, Scott Martineau, Brita Nilsson, Karen Janney, Charles Everson, and George Haddad.

Bill Gray is a renowned author who believes that his reclusive lifestyle and avoidance of a public image are necessary to protect the integrity and uniqueness of his work. He feels that interacting with large numbers of people will influence his thought processes and result in a negative impact on his writing.

Scott Martineau is Bill Gray's live-in assistant. He is in agreement with Bill regarding the negative impact that public life would have on Bill's process. Scott shares Bill's belief that if a piece of literary work is exposed to the public masses, then the integrity and originality of the work (as well as that of the writer) can be compromised and corrupted.

Brita Nilsson is a photographer who is the first person to convince Bill to come out of his self-imposed seclusion and allow her to photograph him for a piece she is working on about authors. She speaks with her editor/publisher about Bill, ultimately setting Bill on a course that will alter his entire life. Brita then sets out on her own path that lands her in a situation she is completely unprepared for.

Karen Janney is Scott Martineau's romantic partner and a former member of the cult of the Reverend Sun Myung Moon. She left home against her parents' wishes to travel to New York City, where she took part in a ceremony to unite her with a member of Reverend Moon's Unification Church. Through Scott, Karen meets Bill and begins working for him. After Bill leaves the country and Scott becomes involved with Brita Nilsson, Karen disappears into the city's homeless population.

Charles Everson is Brita Nilsson's editor and publisher. He is looking for a way to create sensationalism to draw attention to the plight of a young poet who has been kidnapped and is being held hostage by a terrorist cell in war-torn Beirut. He convinces Bill to come out of seclusion and take up the cause.

George Haddad is the terrorist who is responsible for the poet's kidnapping and for the bombing in London that Bill narrowly escapes. He later becomes involved in Brita's life.