Triptych

Google definition:

1. a picture or relief carving on three panels, typically hinged together vertically and used as an altarpiece.

   "a triptych depicting the Crucifixion"

   • a set of three associated artistic, literary, or musical works intended to be appreciated together.

     "a triptych on the theme of the holocaust"

Image examples:

 

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Ours will be a bit different from these as it has to a) show a narrative and b) be read/displayed in a nonlinear fashion.