From the Saturday Stumper

Today’s Newsday Saturday Stumper, by Frank Longo, is a tough one. Much trickery along the way, and some sheer difficulty. What was the name of J. Edgar Hoover’s fourth successor? Not a name that one can easily derive from crosses, not without already knowing the name.

I especially like the clues for 18-Across and 59-Across, each ten letters: “It won’t click beyond a circle” and “Tall twin, say.” No spoilers; the answers are in the comments.

Finishing the Saturday Stumper once again feels like cause for minor self-congratulation.