The case goes to LAPD detective Milo Sturgis, assisted by Dr. Alex Delaware, an old friend and psychological consultant.

The two find out that similar eye mutilations were infamously performed in the case of a family mass murder some years ago, and the culprit is now in the same facility where the female doctor worked.

Monster was first published in hardback in the United States in 1999 through Random House, accompanied by an audiobook adaptation narrated by John Rubinstein.

[4] Sales for the hardback and paperback editions were favorable enough to place it on the New York Times Best Seller list for the weeks of December 26, 1999 and October 1, 2000, respectively.

[6] Michael Harris reviewed Monster for the Los Angeles Times, criticizing Kellerman's handling of politics, stating that it wasn't the author's strong point and that the book's villain did not seem clever enough.