"A Riddle a Day Keeps the Riddler Away" marked the return of the show's debut villain, Frank Gorshin's Riddler, this time in league with the River Rats gang but still working below ground. The title refers to a phrase that the Prince of Puzzlers had long ago admitted to Batman, that as long as he continues to dish out riddles he hasn't yet reached the end of his reign of terror. Reginald Denny (soon to play his final role in the Batman feature film) plays King Boris, newly arrived in Gotham City, sparking a series of riddles and small time crimes leading up to one huge caper. From a gorgeous beauty queen (Joy Harmon) to the King's Queen of Freedom, there's no end of puzzles from the Count of Conundrums, baiting the Dynamic Duo to his lair at an abandoned waterworks, where a cocoon of silk traps them like a spider's web. Both are attached to drive shafts that rotate at 1000 revolutions per second, enough of a centrifugal force to tear the bones from their bodies. Familiar faces in this episode include John Archer, later seen opposite Eli Wallach's Mister Freeze in "Ice Spy," John Hubbard, and especially Tristram Coffin, veteran of the 1943 Batman serial, as well as the 1950s Superman TV series.
