He is the anti-heroic deuteragonist to Norman Jayden, although, he is also one of the two secondary antagonists in Heavy Rain.
He was assigned to work with FBI agent Norman Jayden in tracking down the Origami Killer. Unlike Jayden, Blake has ruthless methods in dealing with crime such as beating an innocent civilian that he accuses of being a criminal and jumping to conclusions too quickly.
The only good relationships he has with are with Ash, his boss Captain Leighton Perry, Grace Mars, and Scott Shelby, in contrast to his hostility to the three protagonists, Ethan Mars, Madison Paige, and Norman Jayden.
In Heavy Rain
Meeting Norman Jayden
Norman meets Blake in the junkyard to look for some clues in the place. After some questions, the latter says that he is busy and that he and Norman should talk later in his office. When Norman asks if he's allowed to investigate, Blake agrees to let him investigating for clues.
Questioning Ethan Mars
Blake and an officer named Ash (if Norman didn't take the Triptocaine, he would join) interrogate Ethan of what happened. Afterwards, he let Ethan go and plans on contacting him if he has more questions. When Ethan asks if the Origami Killer got something to do with Shaun's disappearance, Blake claims that his son runs away and will be found in two hours. If it's true, he has four days to find him.
Capturing Ethan Mars
Blake and Norman are waiting for Ethan to come out and arrest him. The latter, however, is not convinced that Ethan is the Origami Killer.
At first, Norman questions Ethan in order to save Shaun. However, he gives up, causing Blake to interrogate and beat Ethan up. Norman can either take action or not; if he does by pushing and punching him in the face, Blake would pull a gun on him, which Norman warns him that if he does that, he will be fired. Knowing this, Blake orders Norman to leave before he plans to kill him.
History with Scott Shelby
When Scott, along with Lauren, is caught, Blake frees him. It must be because both of them have great history since Scott is in the police force. Interestingly, he is the only protagonist Blake is acting nice, contrasting the hostility to Norman.
Possible suspect of being the Origami Killer
While Norman is having a dead end to the investigation, Blake arrives and tells him to leave since the police now knows that Ethan is the Origami Killer. However, Norman is not convinced of that and calls Blake an "unbalanced psychopathic asshole". He takes that as a compliment and leaves.
If Norman starts accusing Blake, he would put him at gunpoint, which Blake is infuriated by this. His boss, Captain Perry, is angered of what Norman did and takes him off the case.
If Norman solves the case, Blake would see him in a rush, causing him and the police force to follow him.
If the four protagonists ended up together in the final chapter, he and his boss, Captain Perry, are not included in the news report.
If Ethan is killed while Madison and Norman are around, he and Perry are suspended for an indefinite period.
The only ending he appears in is "Uploaded". In the ending, he rejects his boss' invitation to go to Norman's funeral, claiming that he doesn't see much of Norman, and his boss allows that. When Blake asks of what to do with Norman's sunglasses, Perry replies to let him do anything he wants with it. While doing some work, Blake puts on the ARI, and is send to a virtual reality. At first he enjoys it, then suddenly an illusion of Norman shows up, frightening him in the process. It is implied that he will be haunted by the illusion for the rest of his life even without the ARI.