Mae Feinberg is the second wife of Dr. Edward Feinberg, who she met when she was a student of his 14 years prior to the episode's events. At the time of their affair, Edward was married to his first wife, Sarah, and knowing that Edward wouldn't end his marriage, Mae broke into the Feinberg home and killed Sarah, shooting her twice in the back. The villainess dumped the gun inside a pond after the murder, and in the three years that followed after Sarah's death, Mae married Edward.
Mae had been married to Edward for 11 years entering the episode's events, which had Luis Cruz falsely accused of the murder of Sarah Feinberg, and facing execution in two days. Luis' friend, David Renaldo, had been attempting to prove Cruz's innocence, prompting Mae to hire private investigator Pete Koch to kill him, which he does with a bomb in a briefcase. Koch later went through Renaldo's briefcase and found proof of Cruz's innocence, and following this, the evil Mae shot and killed him to cover her tracks and keep her villainous secret hidden.
Edward ended up being accused of the murders, but Mae was revealed as the true killer when the news broke of Cruz's execution. Patrick Jane caught a glimpse of Mae's heel persona when she was shown actually smiling and feeling triumphant over the news, as Cruz's execution meant that she got away with murder; all the while, Edward expressed grief when Jane told him about Cruz. After the charges against Edward were dropped, Mae was confronted by Edward after Jane informed him that she killed Sarah. Mae finally admitted to killing Sarah, stating that she "did it for us." After her confession, Jane and company drove up and arrested Mae, while also revealing that Cruz was not executed at 10:00 like Mae thought. The clocks were all set forward to trap Mae, and Jane planted a bug in Edward's pocket, which recorded Mae's confession.
- Jud Tylor also played villainous angel Adina on Supernatural.
- Mae Feinberg is mostly similar to Body of Proof villainess Stacey Harrington. Both of them fell in love with married men and killed their crush's wives in order to replace them. They also continued committing murder to keep their evil secrets hidden. One glaring difference is that Stacey's relationship with her future husband began after she murdered his first wife; Mae was an adulteress who dated Edward and later killed Sarah so she could marry him.