Reid determined that he was in a shed in a cemetary, so he gave the clue to the team through the internet cam, and when they used to clue in relation to where the last murders were committed, they were able to locate him. They found him when the unsub was forcing him to dig his own grave (after he admitted that he had "sinned" by locking his mother away). Reid got the gun in a struggle and shot him. Then, at the end, Gideon was going to walk Reid out, but he told him that he needed a minute. When Gideon left, Reid got the bottles of drugs that the unsub was shooting in his arm, so I guess we're going to have an addiction plot with him now.
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