The SS
Pentallian was originally going to have the name SS
Icarus. This was changed after the producers learned of the film
Sunshine, which also involved a spaceship named
Icarus falling into the Sun. Several elements of the episode had been reused from previous episodes. The stasis chamber is adapted from the prop used as the MRI scanner in "
Smith and Jones", according to associate production designer James North. Likewise, the spacesuit the Doctor wears was previously seen in "
The Impossible Planet" and "
The Satan Pit" and has since been repainted, according to producer
Phil Collinson in the online audio commentary for "42". On 12 May 2007, the BBC website published a text-based "exclusive prologue" to the episode. Written by
Joseph Lidster, it details the reactions of one of the characters, Erina Lissak, a recent addition to the crew of the
Pentallian, as the ship's engines stop, a countdown to impact begins, and she unexpectedly meets the Doctor and Martha.
Doctor Who Magazine reported in the preview for this episode that the title "42" was chosen for the fact the episode is set in approximate
real time. Producer
Phil Collinson added in an episode commentary that the name was a reference to the real-time US television series
24. Chibnall goes on to compare the episode itself to "
The Satan Pit", at least from a visual standpoint.
Cast notes William Ash later played Sam in the
Sixth Doctor audio drama
The Condemned.
Vinette Robinson later played
Rosa Parks in the
Thirteenth Doctor episode "
Rosa" co-written by Chibnall, who by this time had become showrunner. ==Broadcast==