You and your friend Laura attend a movie theater that shows horror movies. Unfortunately, you end up getting sucked into whichever of the three movies you watch, and you must figure out how to survive the film and escape back into the real world.
Invaders from the Big Screen provides examples of:
- And I Must Scream: The film House of a Hundred Horrors has several bad endings where the siblings, John and Wendy, turns out to be evil, where they then steal your 3-D glasses and escapes from the movie, leaving you permanently trapped in a horror film.
- Animal Stampede: The giant ape movie set in a jungle have a bad ending where you get squashed by a stampeding herd.
- Cannibal Tribe: Subverted if you choose to enter Going Ape in Blastovision; you can encounter a hostile tribe, but it turns out they're actually vampire extras from the horror movie playing next door working part-time. Makes no difference, because they eat you all the same.
- Cool Shades: The hero from the Agent Z movie is described as wearing cool sunglasses in his action scenes. In the good ending where you help Agent Z defeat Dr. Aqua, therefore completing the movie and being granted a chance to return to the real world, Agent Z will give you and your friend Laura extra shades as "souvenir" from the movie universe.
- Covers Always Lie: The cover shows the giant ape from Going Ape in Blastovision playing in a crowded theater, in front of a panicking crowd. But if you chose the giant ape storyline in the book, you realize the theater to be empty save for you and your friend Laura. Also the cover replicates the ending of the original King Kong by showing the giant ape being attacked by airplanes in the city — a scenario that never happens at any point in the book.
- Dressing as the Enemy: One of the scenarios from Agent Z vs. Dr. Aqua have you infiltrating Dr. Aqua's lair by disguising yourself as a humanigators. You might end up having your disguise blown... while in a room full of hostile, hungry humanigators who had no problems with eating human.
- Giant Foot of Stomping: Choosing the giant ape movie have a bad ending where the ape steps on you without noticing.
- The Great Serpent: Partway through the giant ape movie, you can come across the ape fighting a massive serpent.
- Half-Human Hybrid: Dr. Aqua's minions from the Agent Z vs. Dr. Aqua movie are humanigators — half-human, half-gators. A bad ending have you being turned into one of them in the process.
- Here We Go Again!: In one path, you may successfully survive the House of a Hundred Horrors movie, but the cast promises to see you again "soon" and you then come across a poster for the sequel. In another ending, you save a kindly old lady from vampires and promise to visit her again, only to discover that she is a werewolf.
- High-Voltage Death: While being trapped in a flooded room full of humanigators, you risk knocking a live television into the water... while you're standing in it.
- Instrument of Murder: To escape the horror film, one of the routes you must take is by playing a piano in a room full of instruments in order to get a clue. Play the wrong note, and the instruments will all come to life to kill you and your friends, you being the first victim as the piano's teeth turns into real teeth and chomps you down.
- Karmic Jackpot: The horror movie scenario have you helping a living portrait without eyes by repainting eyes on his face. The portrait then rewards you with a vital clue that leads to the best ending in that storyline.
- King Kong Copy: One of the three movies you can pick, Going Ape in Blastovision, is a King Kong-esque adventure movie revolving around a giant ape in an uninhabited island. Entering said film will have you encountering other giant monsters and hostile natives, much like it's namesake.
- Living Drawing: In the horror movie scenario you can come across an art room filled with unfinished drawings, all of which are alive. One painting is 99% complete, save for the eyes, and you'll need to repaint the eyes back in order to get a vital clue.
- Moon Logic Puzzle: One choice is determined by whether or not you know the meaning of the word "pince-nez", but you continue with the story only if you don't know — if you do, you get a bad ending.
- Never Trust a Title: The title Invaders from the Big Screen implies that movie characters are going to escape from the cinema screen, and invade the real world. Aside from one scenario, it's the opposite that happens.
- Pepper Sneeze: You come across the giant ape from the King-Kong-knockoff fighting a giant snake, and you can help the ape by grabbing nearby pepper plants. The question, however, comes from the choice of whether you should make the ape sneeze, or the snake. It's the ape, the book even lampshades "do snakes even sneeze?"
- Primate Versus Reptile: The King Kong-knockoff film has a scene where the giant ape has to do battle with a giant snake, in a Shout-Out at the 1976 King Kong film. Figuring out that since you're in the giant ape's movie, you'll need to find a way to help the ape win the fight, so that the movie can end for you to escape.
- Ret-Gone: You can escape Agent Z vs. Dr. Aqua, but one outcome from that storyline ends with you returning to the real world and finding out the movie no longer exists because of your intervention.
- Time Stands Still: The horror movie scenario have you promising to help a Living Drawing without eyes to repaint eyes on his face, in exchange for an important clue. But if you turned against your word and tries leaving without helping the portrait (with a poor excuse "you're short on time!") the portrait then curses you to be frozen in time for an eternity. It's a bad ending that borders on Video Game Cruelty Punishment.
- Trapped in TV Land: The very premise of the story, where a pair of enchanted 3-D glasses transports you and a friend into one of three movies, and you must find a way to leave.
