The Spring (2000) on Netflix

While driving on vacation with his son Nick Conway in a lonely road, the widow writer Dennis Conway helps a young couple that crashed their classic car out of the road. Dennis uses his van to tow the car back to the road and later Nick finds a duffel bag with an address forgotten by the couple on the ditch. They drive to Springsville to return the bag and after locating the house, they spend the night in town. On the next morning, while waiting for the breakfast, Nick has an accident with a logging truck in the gas station and breaks his leg. They are forced to stay and Nick has a crush on Dr. Sophie Weston that is treating his son. When Dennis discovers that the dwellers do not get old or sick due to the water of the local spring, Dennis asks Sophie to convince the council of the town to stay in Springsville. However, when he discovers the dark secret of the one hundredth birthday party of the locals, he evaluates his decision.