Episode 6 of The Witness is about see-through panels with two starting points, where two lines get drawn at once. One by the trees goes green early. The next one, out over the water, takes up most of the video and is still unsolved when Basket leaves for a desert full of hexagon panels. The video ends in front of a sandstone building with a gold disc on top.
Two lines at once
The video opens on a glass grid panel between green trees, with two round starts on its left side. Two lines go in together in matching shapes, and the panel turns green. "Perhaps we have more of these."
The panel over the water
The next panel stands on a post at the water's edge, with a small rock showing through the middle of the glass. "There's different ways you can look at this thing when you're trying to solve it." Walking close snaps the view to one angle, and a look back at the tree panel turns up a detail: "the tree was actually blocking my view."
The rock gets no such help. "Alright, let's be systematic about it." Straight across doesn't work. Then come lines bending up and down around the middle, two-high steps, full blocks, stair steps one way and then the other. A viewer suggested a path, and the commentary tries it step by step: "up to the top, over one, down one, over one, down and over. Nope."
"Everything else made so much sense." After about ten minutes on it: "I will return to that puzzle."
The desert
Next is a desert of sand and pale stone, with a little elevator "we can't do anything with." Dark red panels on posts show a black hexagon with spokes from the center, each wired by a black cable. "Before I just sort of brute force it, I am trying to see if there is anything around that would give me a hint." Lines go around the hexagon and in and out of the center, and nothing lights.
Under one structure is a locked door. Cables run to black square panels that are all dark. "I think we're trying to actually power that using these solar panels that are all off." Scaffolding climbs the stone around them.
Where it ends
After a few more passes at the hexagon panels comes "it's also possible I'm not supposed to be here yet," and then "I think I'll try coming back here another time, but now I know this thing exists." Basket walks up to a sandstone building with carved rays and a gold disc over its doorway, turns to look out over the desert, and the video ends. The water panel and the desert hexagon panels are still unsolved.
