Books like The Whispering Room
Dean Koontz
The Whispering Room is 529 pages, about 9 hours 42 minutes at 250 words a minute.
12 books to read next
How long each takes
Child of God 3.6 h Every Last Lie 7.0 h 
Sometimes I Lie 6.7 h 
Death in Her Hands 5.0 h 
Play Dead 9.9 h 
Brother 6.0 h 
Consumed 5.9 h 
El Día Que Se Perdió la Cordura 8.4 h 
The Silent Patient 6.5 h 
Uncle Silas 8.8 h 
Hannibal 9.4 h 
Sister, Sister 6.8 h Bar height shows length. Estimated at 250 words a minute.