Some Great PBO Eyes
Not all eyes are blessed with hardcover publication. In fact, some of the genre's very best eyes never saw it, or only had a brief taste of it after years of slogging it out on the paperback racks of a million drugstores and bus stations. Paperback publication, of course, lacked the prestige of hardcover publication, and many a great series has slipped away because of it.
Here, then, some great private eye series that first saw print as PBO's. Those marked with an asterisk eventually made it to hardcover publication.