Begin by reciting the Mata Nui / Makuta World Myth and Tahu’s awakening on the beach from the first book, then explain the basic original concept; biomechanical warriors on a tropical island protecting tribal villagers from a darkness infecting the rahi (animals) on the island named after their god. If you want an elevator pitch: It’s Star Wars crossed with AvatarTLA crossed with Transformers, packaged in a Maori cultural aesthetic and infused with light Christian themes. Also be sure to define Bionicle as Biological Chronicle if he asks what it means, so then his mind will be blown by the name’s hidden implications all along once you reveal the Mata Nui Robot when you get to the end of '08.
As you dive into the basic worldbuilding, story beats and characterization from the first year, explain how they tied into the marketing decisions for the toy line. For example, you should note that the idea of the Toa collecting masks and knocking infected masks off of Rahi was included in the story to encourage kids to collect the masks from sets and from mask bags, as well as to advertise the innovative designs of the gear functions. If/when you describe how Takua’s POV ran parallel to the Toa’s, explain that MNOG was a gateway drug into the franchise for many fans, letting them explore the world personally. These carefully considered marketing decisions paid off for LEGO, as Bionicle along with Star Wars generated necessary sales which would help to save the company from bankruptcy. Use promotional images, artwork and the CGI commercials to showcase what you describe, and you may also want to show him the original comics.
As a way to simplify the different eras of G1, you may want to compare them to the different stages of the Star Wars saga: The Golden Years are akin to the Original Trilogy; a classic heroic monomyth opening on sand. The Metru Years are akin to the Prequel trilogy; flashing back to a more metropolitan, dystopian world. The Ignition Trilogy is akin to the Sequel Trilogy; scrapping the OT heroes for ones who are new yet familiar. Another way of putting it is the Golden Years are a simple legend, the Metru Years are a sci-fi dystopia thriller, and the Ignition Trilogy is a run of blockbuster epics. '09 is Gladiator in space and '10 is a nostalgic victory lap with major budget cuts.
Save the Mata Nui robot reveal for the end of '08, but remember to emphasize all of the info hinting at it from the prior years, i.e., make sure he remembers and can differentiate between lore words like Mahri Nui and Karda Nui so when you explain that Karda Nui is named so because it is Mata Nui’s heart, (Karda = Kardius/Cardiac/Cardio = Linguistic reference to Heart,) he will not be totally confused. You should probably namedrop Christian Faber as one of the lead designers in the beginning, but save the pill inspiration for later.
I cannot stress this enough: DO NOT START BY SHOWING HIM THE MOVIES IF YOU WANT HIM TO APPRECIATE BIONICLE AS A MYTHIC EPIC, OR EVEN JUST AS A GOOD FRANCHISE. All of the Bionicle movies are terrible. I will fight anyone on this, people only like them because of nostalgia, which mostly comes from Nathan Furst’s soundtracks. The animation style is ugly, most of the voice-acting is embarrassing and the dialogue is worse. Their only redeeming qualities are the aforementioned soundtracks, which I actually would recommend using to help set the mood at times.
As for G2, the story is thin and the atmosphere is practically nonexistent so the best things to focus on are the greatness of the 2015 sets, and how the initial wave of community hype was rapidly replaced by an equal and opposite reaction of disappointment and vitriol.
