The Outer Limits: It Crawled Out of the Woodwork (TV)

An energy-being, created by accident, overruns an experimental power station. Personnel whom it has killed, are restored to life, with electronically-controlled pacemakers and are forced to service the being, by a fanatical scientist, who pretends to be looking for a way to destroy it. After the force kills a security guard, and a newly-hired scientist, 2 men; the first being the psychologically disturbed brother of the recently-killed hire, the other, a cop, attempt to uncover the station's secret.