|“||It's a plague mask. Doctors used to use them, they thought they filtered out disease. As a matter of fact, when they arrested Meadows he was wearing one. They had to hold him down to rip it off.||”|
|“||The masks. You said they practically had to tear it off of him, right? (...) So if he's tied to something (...) I'll take that as a yes.||”|
Avery Meadows' plague masks were four plague masks that belonged to Doctor Avery Meadows.
In his practice as a doctor, Avery Meadows used the masks to protect himself from disease. Meadows was so attached to his masks, that the authorities had to forcibly rip one off of his face when he was arrested. The masks were left in Meadows' home which doubled as his treatment facility.
After his death, Meadows become a violent spirit. Due to Meadows being cremated, his ghost became attached to his plague masks since they had been such a big part of him. Meadows' ghost's appearance included him wearing one of the masks.
In 2017, after entering the Meadows' house on a dare, the masks were found by Shawn Raider and his friend Evan. Evan pushed his friend to steal one of the masks, enraging Meadows who attacked the teenagers, killing Evan and traumatizing Shawn. The stolen mask remained in Shawn's backpack as he returned home. Unwilling to speak in his state, Shawn drew pictures of the mask.
While investigating the case, hunter Dean Winchester noticed Shawn's drawings of the mask. After learning from Mike Raimos where his two friends had gone, Sam was able to identify Meadows as the culprit and Dean's attention was drawn by a picture of a plague mask. Sam explained the plague mask's history in medicine and its connection to Meadows personally.
The night after Shawn's escape, Meadows manifested in his room and possessed the teenager. Meadows forced Shawn to put the mask on and return it to its rightful place in his home before Meadows forced Shawn to commit suicide using a drill.
While searching through Meadows' house, the Winchesters found the treatment room with the masks on a shelf. Upon seeing the masks, Dean remembered that Meadows practically had to have one of the masks tore off of him and realized that the masks were most likely what Meadows was attached to. As Sam attempted to keep Meadows' ghost out, Dean threw the masks into a trash can and poured lighter fluid upon them. As Meadows entered the room, Dean ignited the masks, causing Meadows' ghost to go up in flames. After Meadows' destruction, the Winchesters left the masks burning in the trash can and left the room.
While talking to the ghost of Shawn, Dean learned of how he stole the mask and was forced to wear it back to the house by Meadows.