The seeds for this were 1A1AA "vast ____" (what then-FCC Chairman Newton Minow called television)[---------] and 4D4DPoet whose most famous poem is "The [1 Across]"[-------] (I'm still on a major poetry kick), but I was thrilled to include 10D10DBullwinkle's 55 Across[-----------] as well, after triple-checking the spelling. This one's difficult, but I hope you find it worth the effort!