Back on the North Shore with nothing left to try, Basket finds a key hidden in a book, opens one bar of a post in the middle of town, then turns to a walkthrough.
Basket keeps failing at the slatted panel by the locked door, searches the whole town for a missing piece, then asks for a hint that points to the periscope.
Basket finishes a row of button posts, gets a brass panel of slats out of a pedestal, and spends the episode on the winding blue line it shows by a locked door.
Basket reads glowing writing on a wall to crack the symbol grid, rides the floor down to a basement, and charges a blue crystal torch with an eel from the well.
Basket walks through a newly opened gate into the Watchtower area, lights a lamp with the torch and a telescope, and ends by aiming the telescope at a lens set in a window.
Basket explores the Crystal Lab, finds a sheet that turns five symbols into numbers, and tries them on a grid of symbol buttons, but one symbol never turns up.
Basket finds no use yet for the new tool, then spends most of the episode on a frame of sliding wooden blocks by a building in town, and gets the block through at the very end.
Basket starts Quern on an island of stone and wood, fits a missing stone piece into a door, and works out a ring dial on a barred gate from the drawings in the professor's letters.