each PUZZLE will lead you
The Big Bang Theory Season 7, Episode 3
Not the cube, but the PUZZLE of
why I couldn't solve the cube.
The Big Bang Theory Season 12, Episode 19
New PUZZLE, Ma!
The Big Bang Theory Season 4, Episode 19
"When you're doing a PUZZLE,
The Big Bang Theory Season 7, Episode 3
I'll just finish my crossword PUZZLE.
The Big Bang Theory Season 1, Episode 1