There are 1 book by Marcus O'Brien on BookOrb. A strong starting point is Innocent Bones (2022). The bibliography below is in publication order, with series grouped in reading order.
Standalone books
Frequently asked questions
How many books has Marcus O'Brien written?
BookOrb lists 1 book by Marcus O'Brien.
Where should I start with Marcus O'Brien?
A good starting point is Innocent Bones (2022).
What is the Marcus O'Brien books in order list?
In publication order: 1. Innocent Bones (2022).