Rob Weychert’s review published on Letterboxd :
The Crazies arrived in 1973, five years after George Romero’s auspicious debut (Night of the Living Dead) and five years before his masterpiece (Dawn of the Dead). As a low-budget doomsday thriller, it lands directly between those two films as well, making great use of what he learned from Night’s confined space (paranoia, a winking cynicism, and subtle but devastating irony) while sketching out in long form what he would later condense into Dawn’s apocalyptic first act (the failure of institutional crisis management).
In terms of overall quality, The Crazies is definitely the least of the three films, but the one area it succeeds above the other two is in its use of dialogue. Romero has little faith in humanity’s capacity for conflict resolution, so his characters tend to spend a lot of time arguing. It can be overbearing and repetitive (as in the case of 1985’s exhausting Day of the Dead), but The Crazies’ heated debates manage to develop characters, generate suspense, and keep the plot moving at a good pace without ever feeling too artificial.
Of course, what superficially differentiates The Crazies most from Romero’s best-known films is its lack of zombies (strictly speaking, anyway). But any good zombie movie knows that zombies are but one of many available excuses for us to bring about our own ruin, and this one does too.