Glistening Tears (光る涙 Hikaru Namida) is the twenty-first episode of Phi Brain: Kami no Puzzle Season One and the twenty-first episode of the anime series overall.
As Kaito experiences strange occurrences in which he loses focus of everything else when he glances at puzzles, Cubic reveals this is the result of Kaito's brain speed reaching abnormal levels, advising him not to solve puzzles anymore. As Kaito ignores his advice and prepares to face another Fool's Puzzle, Cubic asks for Souji's help in hacking into POG's network. Although Kaito is able to quickly solve the puzzle, he remains unable to see anything, but Nonoha arrives and helps him return to normal. As Cubic and Souji successfully hack into the POG network, Baron follows Rook to where Jin is held captive, finding that Rook also has an Orpheus bangle.