Engrossing, riveting (8)
I believe the answer is:
gripping
I believe this clue is a double definition.
'engrossing' is the first definition.
(I know that engrossing can be written as gripping)
'riveting' is the second definition.
(I know that riveting can be written as gripping)
(Other definitions for gripping that I've seen before include "as one's vices may be" , "Sensational" , "Holding tightly" , "Grasping" , "Suspenseful" .)