Brian Austin Green revealed that an alternate ending was filmed for this episode in which John, while wearing the Red Kryptonite heart, voluntarily chose to reactivate the chip and become devoid of emotion following Lois' rejection. Green also revealed he initially decline to reprise the role due to the fact the script wasn't completed at the time of the offer. He expressed dissatisfaction with the final product, while also expressing a willingness and desire to return to the series in the final season. While Corben did appear in Prophecy, Green did not return and body double was used in his place. Green later speculated that his unfavorable remarks on the episode were responsible for his not being invited back for the final season.
When Lois enters the basement of the Talon for the first time there is a sign for Lobo's Road trip, a Character of the DC Universe
This episode marks the introduction of the arctic version of super breath as one of Clark's powers, although Clark used his superbreath to cool down Lois' coffee in "Rabid".
John Corben appears for the first time in "Savior" and was defeated by Clark in "Metallo", where he lost his kryptonite heart and it was found by Tess Mercer. Tess gave the kryptonite heart to Toyman in "Echo", and ordered him to figure out how it works.
This is the first time Professor Vale is mentioned. Here, Lois refers to him as Dr. Vale.