it an above-average thriller 
(ROOT (S (NP (PRP it)) (NP (DT an) (NML (ADJP (JJ above) (HYPH -) (ADJP (JJ average)))) (NN thriller))))
(ROOT (S (NP (PRP )) (NP (DT ) (NML (ADJP (JJ ) (HYPH ) (ADJP (JJ )))) (NN ))))