Super Mario Odyssey has plenty going on, and if you're confused about how it all ties together Nintendo has a quick little primer for you.
The principle of the game is that Bowser has kidnapped Peach and plans to marry her against her will. Bowser's a creepy bugger. So as you'd expect, Mario trots the globe possessing people, plans, Goombas and cars with Cappy, resulting in all kinds of hijinks.
The game's supports two-player co-op, and has a feature designed for people who are new to gaming called Assist Mode. It basically puts a series of guided arrows on the screen to help people from getting lost, as well as making respawning easier should someone fall to their death.
Beyond that, the five minute trailer goes through some of the various kingdoms, covers the basics of progression, and how the Odyssey works (it's an airship).
By the way, there's also some wedding-styled Amiibo due out on October 27 (when Super Mario Odyssey launches). Bowser's one looks particularly sweet, as does Peach.
All existing Amiibo is compatible with Odyssey too, with each one showing you the location of a Power Moon on the in-game map.