Liza, a late 20s-early 30s woman accompanied by her younger self, navigates the last day of the world by having conversation with people she's wanted to have but feared having.
The movie has a 6w7-ish flavor. Liza finds herself in Alice-in-Wonderland-esque conversation that are absurd and approached matter-of-factly, in the way of healthy 6s, nonplussed, seeing things like as are ("We all know we're dying tonight, and yet here we are having this conversation. Huh. Well, let's talk.") The absurdity and realism are both enhanced by it being bright daylight for the majority of the movie — a physical metaphor for the sharp clarity of awakeness that comes when we confront our fears and embrace mortality without flinching.
Liza's confrontation with all of her fears is rather a point blank 6 story. Identify a fear, then go meet it head on. The growth journey of the 6, plain as day. And here, in the conceit of the movie, accelerated by the acceptance of impending doom. There is no such thing as "Security," so might as well lay it all out on the line and stop being a scared person hiding from life. This is the fundamental 6 lesson, and with each confrontation, a catharsis, after which Liza experiences a greater willingness to see and know and experience her own value (embracing the missing piece of the 6, the high side of 3.) The final moment of reconciliation with her younger self is a universal moment, a point of culmination in all healing paths, especially parts work.