18 Twin Peaks Easters Eggs, In-Jokes And References You Need To See
17. ...And On Leland's Coat
In fact, The Black Lodge wasn't even the first time the floor pattern had appeared in the Twin Peaks...
In our opening episode, with Leland Palmer completely overcome with the grief of losing Laura, he begins dancing round the room with a picture of his departed daughter. As his movement steadies and the camera gets closer, we can see that his sport coat comprises the exact same pattern as the floor of the black lodge.
Given the revelation later that (huge spoiler alert) Leland was the one who killed Laura - while possessed by Bob, himself some sort of spirit connected to the Black Lodge - it's a huge, huge piece of foreshadowing.