The episode was released on July 4th 2016 at 9:15PM/8:15PMCT and received a TV-PG rating.
When Lenny holds the gang's annual 4th of July pool party at his house, all seems to go great, until one of Jonah Flenderson's fireworks explodes while he shows it off to everyone. When a nearby house explodes merely seconds later, Lenny and Jonah are left to believe they're at fault.
One of Jonah Flenderson's Congo packages is mistakenly shipped to Lenny's residence (again). When he takes it to Jonah, he learns that the package is a pair of swimming goggles for the gang's upcoming annual 4th of July pool party, which Jonah and his cousin and roommate Martin Anderson are supposed to be hosting. Jonah invites Lenny into his backyard to watch him test out his new goggles, where destroys his "throw away" pool, that he purchased from Flawmart for only $14, that was previously intended for the pool party. Lenny then offers to hold the party at his house instead using his professionally installed pool, to-which Jonah agrees.
The next day, on Independence Day, Jonah Flenderson, Martin Anderson, Harvey Duncan, and Randy Stallone gather at Lenny and Katrina's house for the party. Katrina goes to the store for ketchup while Lenny goes next-door to borrow charcoal for the grill. During their absences, Jonah shows off his "X-02" 600 gram firework to everyone. He explains that he bought 20 of them for only five bucks from a "guy with a really long beard in a shack on the side of the road". Moments later, Lenny returns and finds Jonah holding it not far from the active charcoal grill. Knowing of Jonah's lack of self-awareness and clumsiness (especially when it comes to fire), Lenny becomes panicked and runs towards Jonah to get him to get the firework away from the grill. However, in the midst of the situation, Lenny trips over Jonah, causing the firework to fall out of Jonah's hand and into the grill, where, much to everyone's horror, it explodes and flies away through the sky.
Meanwhile, a house implosion stunt is underway for the soap opera "Silver's Anatomy". Seconds before the explosion, the firework harmlessly lands on a sidewalk and emits no more than a few sparks, evidently a scam dud (this was earlier implied when Jonah mentioned that he bought 20 of them for only five bucks). When the house is blown up, everyone, unaware of the filming and that Jonah has fallen for a scam and received dud fireworks, become convinced that the explosion was actually caused by the firework.
Taking Lenny's kitchen fire extinguisher with them, Lenny and Jonah dash to the site of the house, only to find of course that it has already been blown to smithereens. They become convinced that there were people in the house and have been killed by the two of them. The two flee to an unspecified location until they decide to turn themselves in at the police department. However, upon confessing, the police station desk clerk claims that they have received no reports on a firework implosion. Lenny coaxes the clerk into tuning into the local news, but there is no coverage on the incident at all, on the national or local news. Lenny and Jonah are eventually thrown out of the police station.
The completely dumbfounded duo returns to Lenny's house, where Martin informs them that the explosion was staged and not caused by the firework at all. Jonah learns from this that the firework was a dud and then receives a lecture from Martin regarding too-good-to-be-true sales.
In the evening, the entire gang sits out at a park to watch fireworks. During the observation, Martin realizes, in horror, that he left the cookies baking out on the dashboard of his car and forgot take them out: but it is too late, he returns to his car to find it has burst into flames when cookies began burning. Jonah stands and watches the burning car along with Martin and explains that he left the fire extinguisher from Lenny's house out in the field when the were hiding from police, which took place earlier soon after the house implosion.
Work on the episode's rough draft script began during the production of the previous episode, Unhappy Birthday Martin Anderson, and was temporarily shelved to focus on the completion of Unhappy Birthday Martin Anderson. On June 22nd, immediately after Unhappy Birthday Martin Anderson's completion and release, work on the script continued. The rough draft was completed on June 23rd, with construction of the episode's required backdrops beginning on the same day. Backdrops have taken significantly less time to produce for this episode, with four backdrops (plus an additional, slightly altered version of one of them) created in the same day, three of them within about an hour and a half, with the most complicated one taking about about two hours to complete. This is significantly less time compared to the previous episode, with an average of an entire day to complete a single backdrop, some as many as three to four days. All of these backdrops were for the episode's prologue.
On June 26th 2016, live action fireworks footage was shot for the episode's closing scene. The fireworks that were filmed took place after a Frisco RoughRiders baseball game at Dr. Pepper Ballpark in Frisco Texas.
Audio recording began on June 27th, following two script revisions (meaning the third draft was the one used for the episode), and animation began shortly after that. That night, the episode's prologue sequence, which also includes the theme song, was completed and rendered in fully animated form.
On June 28th, pick up recordings began, as the editing process continued. That same day, there was much trouble regarding Katrina Kyla's design, as it was being deliberated whether or not to slightly alter her character's design. However, her first starring sequence had already been edited, meaning it would be required to replace all of her current character PNG files to accommodate the changes. There are two existing versions of this sequence, each with a different design of Katrina (the rest of the sequence is identical though). The latter of the two was the one used for the final cut, and that version's design of Katrina was used for her subsequent appearances.
On June 30th 2016, most of a pool party scene had been completed. Additional files had to be created for characters featured in swim attire and are totally separate from those of their normal attires.
Much pressure was placed on production of this episode. As a fourth of July themed episode, it has a very specific deadline to meet. As many as 6-8 hours of work a day was placed on the episode, one of those days for a two and a half minute long pool party sequence alone. Regardless, episode production proved to be significantly faster than the previous episode, Unhappy Birthday Martin Anderson. One of the character's art conceptions, both original and additional positions, were completed in a record 45 minutes, as opposed to Unhappy Birthday Martin Anderson, where characters took an average of 1-2 days each to create, excluding additional positions. Furthermore, backdrops were being completed each in about an hour, with each of the previous episode's backdrops taking a minimum of one day, some of them up to four days, to complete. Finally, one of the pool party sequences was completed in half a day: the amount of work required for the sequence was about the same as the closing sequence to Unhappy Birthday Martin Anderson, which took three days to complete. In comparison, "Unhappy Birthday Martin Anderson" took a total of four months to complete, while "Fireworks" only took two weeks.
Editing continued all day July 3rd and even into the Fourth of July afternoon. The episode was finally completed around 5:00PM Central Time on July 4th 2016 and was prepared for release just hours later.
In the wake of the 2016 Istanbul Airport incident, which occurred on June 28th during the episode's production, the episode's story-line was slightly altered to eliminate a plot twist contained in the script. At the end of the episode, when Martin reveals to Lenny and Jonah that the explosion was staged, this was originally supposed to be when it was first revealed to the audience as well. However, the episode was altered to reveal this information from the start, and to portray the characters panicking in their already known to be misunderstood situation. Oddly enough, the changes made to the episode actually call for the adding of scenes, in contrast to most such changes, which would normally call for cuts to be made. Because of the changes, the character "Phil" has a total of three scenes: in the final draft of the script, he only had one.
The episode was released on July 4th 2016. Part of the episode was re-released the following day due to some minor editing mistakes. The episode was again re-released on September 1st 2016 as a single part video, updated from being split into two parts upon original release.
When re-releasing the episode, Cosby had considered getting rid of Katrina's old design by replacing her files with the current ones: however, this didn't happen, and the re-released episode retains her original design.
After the conclusion of the show's first season, creator Aaron Cosby listed "Fireworks" as his least favorite episode of the season (while also naming Thanksgiving Kerfuffle his favorite). He especially disdained Katrina's voice, which he later described as turning out to be "incredibly annoying". This decision is partially responsible for Katrina's smaller role that she will play in Season 2, after considering discontinuing the character entirely. Furthermore, plans for her to become a main character have indefinitely been postponed, and she will also not appear in the second season's theme song.
In addition, Cosby also disdained the mouth animations, which he found to be disproportionate and off-timed with the dialogue: this style of animation was also used in the previous episode, Unhappy Birthday Martin Anderson. Subsequently, the following episode, The Biffy Martona Chronicle, would begin using a new mouth animating technique where each syllable of dialogue is animated individually, which, although more time consuming, is much more accurate and realistic. This method of mouth animating has been used ever since.
The episode can be viewed here: https://www.youtube.com/watch?v=8Vx_6kvUbDo
- During the prologue, when Jonah Flenderson is seen outside of costume for the first time, the song "Stayin' Alive" by "Bees Gees" is played: however, the original cut of the episode actually instead used the A-Team theme song.
- Katrina Leggo, Lenny's wife, makes her debut appearance in this episode, making her the first female character to star in the series. Technically, there are two female characters in the episode (the other being Martha, the police station desk clerk), but because Katrina appears on screen first, she is technically the first. She was also created first of the two.
- The pool party scene required the creation of over 50 character PNG files, since every character position in every attire is it's own edited file. Every character in the scene, except for Katrina, appears in some form other than their normal attire, although even Katrina's files count for this as well, since, prior, her side-view art conceptions had not yet been created.
- The fireworks that appear at the end of the episode were shot at the Dr. Pepper Ballpark in Frisco Texas on the night of June 26th 2016. During that same game, the "Hairy Bikers" from the British Broadcasting Company made a public appearance at the stadium and also shot sequence footage before, during, and after the game right before the fireworks.
- The game that was played at Dr. Pepper Ballpark that night was The Frisco Roughriders (home) vs. the Corpus Christi Hooks (visiting). The Roughriders lost 2-9, although both points they scored were in the first inning, while the Hooks still had nothing. It started at 6:05PM.
- The episode marks the first time in the series that four characters appear on screen simultaneously. During the editing stage, each character required two video tracks, one for the character him/herself, and the other for the mouths, meaning a total of eight video tracks were used for the characters alone. The four characters that appear in the sequence are (from left to right) Jonah Flenderson, Lenny Leggo, Katrina Leggo, and Martin Anderson. Harvey Duncan and Randy Stallone were also supposed to appear in the scene, but due to time constraints caused by the episode's mandatory due date of July 4th, they were ultimately left out.
- Sometime after the episode was released, Aaron Cosby stated that Katrina was by far his least favorite character in the episode. He commented that her voice turned out "extremely irritating and annoying". Because she (like every character in the series so far) is voiced by Cosby himself, that means that Katrina is actually voiced by a male, despite being herself a female.
- In December 2016, Cosby listed "Fireworks" as, so far, his least favorite episode, while also listing "Thanksgiving Kerfuffle" as his favorite.
- At the very end of the episode, when Martin's car is on fire, it most likely should have exploded, as the flames would have likely come into contact with the car's gasoline: however, this doesn't happen at all. Due to the shape of the car, the possibility of it being a hybrid has been ruled out. It could, however, be assumed that Martin's car coincidentally ran out of gas as soon as he pulled into Lenny's house earlier that day, meaning there was little to no gas in the tank at the time of the incident.
- As in the previous episode, anytime Martin is shown from the side, his glasses and stethoscope are not there, they are only there when he is shown from the front or back. The art conception files were updated for The Biffy Martona Chronicle to prevent the error from repeating itself.
- There was a slight cropping editing error near the end episode, during the scene when Lenny and Jonah return home from the police station after their failed attempt to confess. The crop change was one frame off and was not consistent with the scene cut. The one frame where the scene is not cropped properly was removed and the following frame was duplicated to take its place.
- California, the state that The Lenny Leggo Show is set in, is one of the strictest states in America regarding fireworks, so it should have been one of the 17 states that banned the X-02.