Director George A. Romero at his best, when he tell us a story about the rising dead and the people that fight against them in order to survive in Night of the Living Dead.
It all begins when the brains of the recently deceased become reanimated, allowing them to rise from the dead and eat human flesh.
How are they coming back from the dead? Well in the movie they talk about a NASA satellite returning from Venus being covered with radiation and due to this it could have caused the dead to rise. Note that this is only left as speculation in the film.
What we do know is if anyone dies during this crisis and their brains are not destroyed they will return as a flesh craving zombie, you can also be infected if your bitten by one of the monsters. The only way to kill them is to destroy the brain - which makes for one great horror film.
As the movie unfolds we see a young women, who was visiting her father's grave taking refuge in a nearby farmhouse. While there , she is met by a man who protects her and barricades them inside. They then later discovery that there is people hiding in the basement and they all come together to try to understand what is happening and to get an idea on their situation.
They soon realize that if they want to survive they need to get gasoline from a nearby pump and put it into a truck. In order to do this they have to brave the hordes of walking corpses that surround the house outside. As the movie sees these characters putting their plan into action, panic and tension arise and that only adds terror to the group and makes it harder to survive.