Harrison Investigation
1 Haunted (2003)
2 The Presence (2004)
3 Ghost Walk (2005)
4 The Vision (2006)
5 The Seance (2007)
6 The Dead Room (2007)
7 The Death Dealer (2008)
8 Nightwalker (2009)
9 Unhallowed Ground (2009)
10 The Killing Edge (2010)
2 The Presence (2004)
3 Ghost Walk (2005)
4 The Vision (2006)
5 The Seance (2007)
6 The Dead Room (2007)
7 The Death Dealer (2008)
8 Nightwalker (2009)
9 Unhallowed Ground (2009)
10 The Killing Edge (2010)
Omnibus editions
The Dead Room / The Death Dealer (2017)
Unhallowed Ground / Nightwalker (2017)
Harrison Investigation Series Volume 1 (2018)
Harrison Investigation Series Volume 2 (2019)
Harrison Investigation Series Volume 3 (2019)
Unhallowed Ground / Nightwalker (2017)
Harrison Investigation Series Volume 1 (2018)
Harrison Investigation Series Volume 2 (2019)
Harrison Investigation Series Volume 3 (2019)