Definition[]
The fourth wall is the notional boundary between a story’s world and its audience—one that, when acknowledged or crossed (through direct address, meta-commentary, interactive participation, or production errors), highlights a work’s self-awareness and brings the audience into the mechanics of its own storytelling.
ARGs and Marketing[]
The most overt fourth wall breakage comes in the form of the many interactive promotional campaigns put on by ABC.
An alternate reality game (ARG) is an interactive, cross-media narrative. Fictional elements of the narrative, often presented as real, include clues that lead players to discoveries that further the game. Five Lost ARGs have been produced as season hiatus activities for fans. The Lost Experience focused on the Hanso Foundation's origins; Find 815 focused on Oceanic Airlines, the Dharma Initiative Recruiting Project focused on the modern DHARMA Initiative, Lost University focuses on Lost, and Damon, Carlton and a Polar Bear focuses on artwork.
Other examples of Lost content accessible in real life include:
- Oceanic hotline, which is related to the DVD extra The Oceanic Six: A Conspiracy of Lies
- Oceanic-air.com, the first official Oceanic Airlines website made by ABC/Lost.
The expanded universe and the deuterocanon may also be considered relevant.
Direct Address[]
A direct address is when a character looks, speaks, or gestures straight “to camera” or “the viewer” acknowledging the audience’s presence. There are two assumedly intentional direct addresses, and one that is unintentional.
Intentional[]
Both intentional addresses come in the penultimate episode of the series, S6E16, What They Died For. It is assumed that these two addresses are intentional, because:
- Two of the three direct addresses occur in the same episode. 
- The episode in question is the final standard episode before the Finale.
- They are seemingly so overt, so as to be nearly impossible for them have to be included accidently.
- The two who break the fourth wall are the arguably most important characters at this moment within the plot and themes of the show.
- The two characters have the relationship of Protector/Heir. 
- Jacob is a transcendently powerful being, whom may have the ability to see the audience.
Jack looks at the camera.
Jack[]
In S6E16 "What They Died For", after Jack says to Locke, "Don't tell him that" and laughs, he breaks the fourth wall for a moment by looking directly at the camera.
Jacob[]
Jacob breaks the fourth wall as he explains what they died for.
While addressing the remaining four candidates, he says, (in reference to the Man in Black)
"I made him that way... and ever since then-- he's been trying to kill me. It was only a matter of time before he figured out how and when he did, someone would have to replace me. *Jacob glances at audience* And that's why I brought you all here."
In this clip, at 0:54 seconds. 
Jacob implicates the viewer by looking at us and implies that he brought us to the island as well. It is up to the audience to replace him.
The non-descript survivor glances at the camera.
Unintentional[]
In S2E1 "Man of Science, Man of Faith", after the N.D. Survivor says to Charlie "But the... but the French woman said...", she breaks the fourth wall for a second by looking directly at the camera.[1]
Meta Narration[]
From a metanarrative perspective, the fourth wall is not only the boundary between fiction and reality, but an element of the story’s self-commentary. It’s the “wall” whose permeability defines the story’s awareness of itself as a constructed narrative. Lost never directly “breaks” the fourth wall—but it does deploy several meta-narrative devices that, while still diegetic, call attention to the fact that we’re watching a highly constructed story.
Episode Titles That Foreshadow or Comment on Storytelling[]
Many titles (e.g. “The Constant,” “The End,” “Ab Aeterno”) gesture toward thematic or structural hints in the plot.
“Previously on Lost” Recap Segments[]
Before each episode, the audience is directly addressed to summarize past events—these directly address the audience’s memory and remind us we’re watching a serialized story.
Flashbacks, Flashforwards & Flash-Sideways Structure[]
Though not fourth wall breaks per se, the radical shifts in narrative time constantly draw attention to the mechanics of the story. By revealing future outcomes or "alternate" realities, the show makes us aware of its own narrative design.
The Church in The End[]
Up until this point, we’ve accepted Lost’s events as “real” within the show’s universe. By placing the characters in a space/time that is after/beyond the “real world”, where logic breaks down, we can see it exists as a narrative staging ground. The characters end up right where they are supposed to- because they are supposed to. The "gods" that would be typically in charge of deciding who gets to achieve afterlife status, are instead replaced by the writers.
Bloopers[]
Bloopers are production errors by cast or crew that are heard or visible onscreen. Continuity errors are bloopers that don't match storylines or timelines from other parts of the same episode or other episodes.
A blooper can be considered a type of fourth wall break because it reminders the viewer that we are watching a piece of media, and because in-universe, there are no explanations for the bloopers if they are to be considered canon to the characters in-universe.
Easter Eggs[]
An Easter egg is hidden content intentionally inserted by the creators. With respect to Lost, such content may be:
- hidden inside either the episodes themselves, where they range from personal jokes, to foreshadowing or development of a plotline or;
- integrated within the retail DVD interfaces as hidden functions, interface behaviors, and full videos, where Easter eggs have become an expected part of this product industry.