Criminal discovered in last chapter. 
( Criminal ( ( discovered ( in ( last chapter ) ) ) . ) )
(ROOT (S (NP (NNP Criminal)) (VP (VBD discovered) (PP (IN in) (NP (JJ last) (NN chapter)))) (. .)))
Criminal is never discovered.
( Criminal ( ( ( is never ) discovered ) . ) )
(ROOT (S (NP (NNP Criminal)) (VP (VBZ is) (ADVP (RB never)) (VP (VBN discovered))) (. .)))