|Episode(s)|| 6.11 Appointment in Samarra|
6.14 Mannequin 3: The Reckoning (referenced)
Dr. Robert operates without a medical license in an apartment above a Chinese grocer. He tells Dean that he stitched up his father, John Winchester, countless times back when he was a legitimate doctor.
Dean pays the doctor and his assistant, Eva, to kill him and then bring him back to life. After the doctor claims a 75% success rate for the procedure, Dean gives him a letter addressed to Ben Braeden and asks him to mail it in case something goes wrong. Dr. Robert takes the letter and then tells Dean he has 3 minutes of death before injecting him with something that kills him. When he tries to revive Dean after the negotiated 3 minutes, he is unsuccessful. He and Eva try a defibrillator and then an adrenaline shot to resuscitate him, and finally succeed in bring Dean back to life after 7 minutes.
When Dean takes out the syringes to induce death and revive him, the masking tape on the kit reads: “Dr. Robert. For Emergency.” It is unknown when Dr. Robert gave him the death-inducing kit unless he somehow keeps in contact with Sam and Dean.