it is a popcorn film , not a must-own , or even a must-see . 
(ROOT (S (NP (PRP it)) (VP (VBZ is) (NP (NP (DT a) (NN popcorn) (NN film)) (, ,) (RB not) (NP (DT a) (NN must) (HYPH -) (JJ own)) (, ,) (CC or) (RB even) (NP (DT a) (MD must) (HYPH -) (VB see)))) (. .)))
(ROOT (S (NP (PRP )) (VP (VBZ ) (NP (NP (DT ) (NN ) (NN )) (, ) (RB ) (NP (DT ) (NN ) (HYPH ) (JJ )) (, ) (CC ) (RB ) (NP (DT ) (MD ) (HYPH ) (VB )))) (. )))