Supernatural (TV series)/Recap/S01/E18 Something Wicked

Season 1, Episode 18:

Something Wicked
John Winchester sends Sam and Dean to a town where pneumonia has started to spread among the children, affecting one family at a time. For some reason, none of the kids respond to medical treatment.

During their investigations they find a handprint, which Dean remembers seeing on one of their father's photographs when they were children. It's a Striga, an Albanian witch, which is draining the kids of their life force. It's only weak when it feeds and hides by disguising itself as a human. It's also one of the few monsters that got away from their father.

After exhausting the few leads they have to no use, they return to the motel where they're staying and find out that the youngest boy of the family who runs the place has fallen ill. While Dean gives the upset mother a ride to the hospital, Sam finds a picture in a newspaper from the 1890s of a group of doctors. One of them is the very same doctor who is currently responsible for the pediatrics ward where the sick children are treated.

While arguing with Sam whether or not to use the older brother as bait for the witch, Dean reveals that the reason their father never caught the witch in the first place was because he disobeyed their father and almost ended up having Sam killed by the witch.

Realizing they don't have any alternative, they ask the older brother to act as bait, and he accepts because of the possibility of it saving his brother. They set up a trap and manage to kill the witch, after which all the children are cured from their illness.

Tropes

 * Big Brother Instinct, naturally.
 * Life Drinker: An immortal creature called a shtriga drains the life force from people, mostly children.
 * My Greatest Failure
 * Red Herring
 * Steel Ear Drums: acknowledged--the boys make a note of telling Mike to cover his ears.