[s12e21] There's Something About Mary Here

Samantha Smith (Mary Winchester), Elizabeth Blackmore (Lady Toni Bevell), David Haydn-Jones (Arthur Ketch), and Mark Pellegrino (Lucifer). Critical Reception

The British Men of Letters use a "bug" (a tracking/listening device) to locate and eliminate American hunters. Sam and Dean eventually find the bug in the Impala. [S12E21] There's Something About Mary

Mary undergoes intense mental torture. By the end of the episode, her brainwashing is seemingly complete when she is ordered to kill a fellow hunter and friend. Mary undergoes intense mental torture

Lady Toni Bevell returns to the U.S. to oversee Mary's conditioning, leading to a tense face-off between her and Mary. Production Credits Director: P.J. Pesce Writers: Brad Buckner & Eugenie Ross-Leming to oversee Mary's conditioning, leading to a tense

Crowley’s attempt to keep Lucifer under his control fails. Lucifer manages to reverse the security system in his vessel, overpowering Crowley and escaping his confinement.

The episode is often discussed by fans for its dark tone and the controversial writing style of Buckner and Ross-Leming, who frequently handle episodes involving significant character deaths or major plot shifts. You can find community discussions and breakdowns on the Supernatural Reddit or browse fan-cataloged details on Archive of Our Own.