Supernatural Season 6 Episode 13 (02/11/11)
Sam and Dean investigate mysterious disappearances in Rhode Island.
As the clues begin to unravel, so does a bit of Sam’s past and his prior activities in the same location.
Turns out, Sam and Samuel were hunting an Arachne looking to breed. Sam uses the local sheriff to set a trap, and in doing so, gets him captured. Sam kills this spider like creature and shoots her victims.
Unfortunately, it was the sheriff, now an Arachne himself, who called Sam back to extract revenge. Sam and Dean are captured but defeat him.
Sam goes into a convulsion, as his soul is being burned and charred inside.