A man's body is dumped in the river after he is killed on the streets.

Weeks later, Alex tells the team about the case. He says the man they are trying to identify, who they refer to as River John, is a 40 year old white male who was shot. The police reported that they found him with a .38 caliber gun with a full clip. He was also found carrying a moleskin notebook that is now illegible. They wonder why the man didn't shoot back. Walter figures that the man was a new gun owner. He says he has a gun and goes to the gun range.

Alex meets with Greta, an art curator, and asks her to take a look at the notebook. Greta says she is busy, but will take a look at it if she has time.

Walter goes to the gun range with Candace. They ask the owner if he recognizes the sketch of the River John. The owner says he came in, but didn't have his Firearms Identity card. He says that the man said he needed to be ready. They meet with a gun range patron who recognizes him. He tells them that the River John was looking to score heroin.