A crop dusting machine from the agricultural pest-control is emitting ultra-sonic waves that are re-animating corpses... <br /><br />A lot have said this is underrated, granted it's overlooked, it atmospheric, moody, has great locations and is genuinely creepy. However, it's shares more with Fulci than Romero. The acting is just about competent, bad dubbing, it has an eerie musical score and a number of suspenseful sequences but it's far from an iconic or cult zombie film. <br /><br />I watched it under the title of 'Let Sleeping Corpse Lie' but whichever name you see the film under don't be mistaken or mislead, it's an average zombie horror movie of its time with nice cinematography. That said, it's a lot better than the low budget DTV zombie films that there's no shortage of at the moment.