thought-provoking and even an engaging mystery 
(ROOT (UCP (ADJP (VBD thought) (HYPH -) (JJ provoking)) (CC and) (ADVP (RB even)) (NP (DT an) (VBG engaging) (NN mystery))))
(ROOT (UCP (ADJP (VBD ) (HYPH ) (JJ )) (CC ) (ADVP (RB )) (NP (DT ) (VBG ) (NN ))))