This was from last Friday's Toughie #538 and the answer is BUNBURYING - B(ook) + UNBURYING.
Bunbury is the name of an invented person used as an excuse for sudden departures and was first coined by Oscar Wilde in The Importance of Being Earnest.
Presumably the O that you had came from entering ONES in 2 down instead of NOES - this would also make 16 across hard to understand as it refers to the answer to 2 down.