Additional dialogue added in post-production included Brock's reference to Miss Shuster and Miss Siegel; they were named in homage to Superman's creators Jerry Siegel (writer) and Joe Shuster (artist).
The cold opening sequence was the longest in the history of the franchise, running a little over nine minutes, until Eve of the Daleks (2022), which had a longer cold opening, running only ten seconds after the start of the title sequence for this story.
The Mind of Evil plays in a cinema opposite Lucy's apartment. This is a nod to the 1971 Third Doctor serial.
The large time distortion fixing machine/device the Doctor is making on the roof of young Grant's building is to fix the local time distortions, which the Doctor admits to being the cause of-referring to The Angels Take Manhattan (2012), in which due to the paradox created by Amy and Rory, the TARDIS couldn't return to go back to New York again.
The story is set in New York, as it served as not only the home of several Marvel superheroes, but it also inspired Superman's Metropolis and Batman's Gotham City.