|Birthdate||October 31, 1946|
|Date of (potential) death||October 6, 2011 (The Doc)|
|Occupation||Drug dealer (former surgeon)|
|Voice||Christian Erickson (English)|
|“||We're going to have some fun together, my darling... I promise.||”|
—The Doc to Madison Paige
Baker is a former surgeon who lost his medical license, and now makes money by selling prescription drugs. He is 64 years old at the time the story takes place. He legally owns the apartment at which the Lizard Trial (the third trial Ethan Mars faced) takes place, but he rented that apartment to Paco Mendez, who rented it out to the Origami Killer. His legal ownership of this apartment is what caused Madison Paige to visit him.
When Madison arrives at his house, she claims to be visiting to buy "Betropen," a fictional drug. Baker allows her in, and offers her a glass of wine. If she drinks the wine, she will be knocked out. If not, whilst Baker is looking for Betropen, Madison will have to search for evidence. If she can find a card for the Blue Lagoon, she will take that card and be able to leave. If she walks too far down the hallway or stays in the house too long (either by not finding the card or not leaving right after finding the card), Baker will knock her out.
If she was knocked out in either scenario, Madison will be tied to an operating table in the basement of Baker's house when she wakes up. Here, Baker reveals his true nature as a psychotic, sadistic, and bloodthirsty man. He has a set of tools (a hammer, various heavy objects, and a drill) that he will use to torture and kill Madison. Before murdering her, he will go upstairs to drive away a person soliciting bibles thrice -- Madison can escape at any time. If she doesn't escape, she will be helpless as Baker kills her. If she escapes, she and Baker will have a fight that will end with one of them killing the other with a circular saw or a drill. Baker plays no further role in the game.
- The Doc - He will be killed when Madison drills into his heart if she wins the fight.
- Adrian's scene in "The Doc" is similar to the climax of the film Urban Legend, where the antagonist has the heroine bound to a table and is preparing to harvest her organs.
- Adrian seems to be a necrophiliac, seeing how he rubs Madison's thighs and generally her body after he kills or thinks he has killed her. His use of a drill (a phallic symbol) as an instrument of torture and murder is further evidence of his paraphilia.
- The man who rings the doorbell is selling bibles, which is a reference to a guardian angel (as he prevents Madison from being killed).
- His voice is very similar to Vincent's, though it is unknown if the actor is the same.
- Adrian is the third person with an optional fight, the first being Troy, and the second being Andrew.
- He bears a strong resemblance to Dr. Christian Szell, the main villain from Marathon Man.
- Even if Madison leaves Adrian's house without killing him, she will still refer to him as "Doctor Death."
- The Doc is played by actor Christian Erickson, probably best known for his appearance in the video game MegaRace as the slightly unhinged host Lance Boyle.
- He is the first character who can kill Madison.
- In a sense, avoiding the fight scene with The Doc will leave him alive and unpunished for his crimes, making him a Karma Houdini potentially.