"The Price" is the 19th episode of the third season of the American television series Angel, originally broadcast on the WB network.
When Lorne informs him of the disturbance at the juice bar, Angel brings the infected man back to the hotel, where he collapses into a pile of human dust.
She plans to rid the hotel of the slugs, until Gavin relays the message that Linwood wants Angel and the others to die for the torment he was put through.
After learning the creatures glow in the dark, Angel shuts off all of the lights in the hotel and tracks the slugs by sound to a large ballroom.
Realizing Fred has been infected, Gunn brings her to the rest of the gang in the abandoned ballroom, saying they need to get her to a hospital; Angel stands in the way, determined to keep more innocents from dying.
In that episode, the Powers That Be send a snowstorm to Sunnydale on Christmas Eve in order to prevent Angel from committing suicide by exposure to sunlight.
The concept of thaumogenesis, a price for the use of magic, is also mentioned in the sixth-season episode "After Life" as the Scooby Gang deals with the ramifications of their decision to resurrect Buffy.