Invasion of the Body Snatchers(1978)
Videos: Trailers, Teasers, Featurettes
Matthew Bennell notices that several of his friends are complaining that their close relatives are in some way different. When questioned later they themselves seem changed, as they deny everything or make lame excuses. As the invaders increase in number they become more open and Bennell, who has by now witnessed an attempted 'replacement', realises that he and his friends must escape or suffer the same fate.
Invasion of the Body Snatchers - watch online: streaming, buy or rent
You can buy "Invasion of the Body Snatchers" on Apple iTunes as download or rent it on Apple iTunes online.