The set location for Lydia's house was owned by an architect. Michelle MacLaren explained that they originally wanted to find a trendy high-rise apartment but it was difficult getting the shots and pertaining that the house was actually set in Houston. Vince also decided against using a legend to indicate the change of location, but they had never used legends before. Vince stated that viewers initially might not realize the Houston location but it would eventually come together in latter episodes.
The last scene, described as creepy by viewers, was actually a part of a longer sequence. It was cut down due to runtime, but Walt and Skyler go to bed and Walt starts trying to initiate sex with Skyler but Skyler is further mortified and does not want to participate so she pleasures him in another way.
Goof: Despite what the opening sequence depicts, an AED will only deliver a shock if the heart is in arrhythmia. It will not deliver a shock if there is a regular heart beat or in flat line.
Madrigal Electromotive GmbH is the multifaceted company that is headquartered in Germany and owns Los Pollos Hermanos. The GmbH is a common German suffix for companies with a limited liability.
The crew used the same Denny's from last years Season 4 premiere, the one where Walt and Jesse head after Gus kills Victor. Vince says they actually paid Denny's to use their restaurant.
The title of this episode could refer to the New Hampshire license plate motto "Live free or die" as Walt also identifies himself with a New Hampshire drivers licence in the flash forward at the beginning of the episode
For the burning of the lab, the crew rented a technocrane that is apparently very expensive because it can be controlled remotely. The crew put down water over everything that was going to be burned and then added white gas. This provided a fire but not necessarily damage to the set, which was made of wood and paneling.
The title of this episode came as the suggestion from AMC's Vice President of Production, Susan Goldberg, probably as a joke, but Vince actually went with it.
One of the writers pitched this line for Jesse at the end of the episode: "Mike is going to be pissed!" But it did not make it into the script.
In the episode podcast, Vince admitted that they were thinking of a "ding-boom" (a bomb connected to Tio's bell) between Tio and Gus since the middle of Season 3. But the writing team objected since they didn't want to kill off Gus in season 3.
Vince Gilligan felt guilty about the season finale synopsis, known several weeks in advance while in the writing stage. He phoned Giancarlo Esposito and Mark Margolis in advance and swore them to secrecy. In an interview, Vince said he had felt like he let Giancarlo down, but Giancarlo took the news in stride, saying whatever was necessary for the story was good enough for him.
In an interview with the New York Times, Vince admitted that there was help from The Walking Dead special effects' staff for the explosion scene.
The friendly neighbor that checked in on Walt's house to prevent a 'fire hazard' is actually Vince Gilligan's mom.
The hospital scenes were all shot at a hospital that was closed down in Albuquerque for a number of years. All of the rooms were real hospital rooms and areas, including the chapel. According to the podcast, they may not be able to shoot there anymore because it might be refurbished back into a hospital.
Steven Michael Quezada hosts a talk show in Albuquerque and many of the cast has appeared on the show. During the podcast, Vince and Aaron stated they had appeared.
As per the insider podcast, a scene was planned where Jesse goes to Saul first before going to see Walt, trying to see if the ricin was indeed lifted. But it was nighttime and there was no reason why Jesse would go to the office during the night when Saul wouldn't be there.
In the podcast, Aaron Paul mentions that he hated driving the RV. It was so sensitive to the wind he says, swaying with the direction of it.
When the writing team were coming up with Saul and Walt's frantic interaction near the end of the episode concerning the man who could make Walt disappear, Vince decided that it might be slightly better to have Saul mention this previously. Luckily, the fourth episode was in filming and it was running a bit short, so they had Moira (one of the writers) add in a short scene with Saul telling Walt about this option.
When Ted hits his head, the oranges that are on the counter roll off. The color orange has been used to symbolize death before.
Goof: Skyler tells Ted to make the cheque payable to the IRS, but for business taxes, the money is actually sent to the United States Treasury and then mailed to the IRS.