THEME: "What?" — four theme answers have that clue; answers are all colloquial ways of asking "What?"
Theme is cute, if slightly wobbly. Obviously, answers were chosen at least in part of symmetricality, so you've got a first person pronoun in 58A: "What?" ("I BEG YOUR PARDON") but not in 20A: "What?" ("DIDN'T CATCH THAT"), despite the fact that the reverse would sound more natural — people say "BEG YOUR PARDON" all the time without the "I" in front, "DIDN'T CATCH THAT" less so. Also, "SAY AGAIN" (45A: "What?") is not a familiar phrase to me, though it was highly inferrable. The phrase, as I know it, is "COME AGAIN?" But again, "COME AGAIN" would screw up your rotational symmetry with "EXCUSE ME" (32A: "What?"). This is what I mean by "wobbly" — the actual answers make me think of different, good answers that weren't used and better ways of phrasing answers that were. Still, it all seems tight enough for an LAT Monday. Also, the overall fill is super solid, especially for a grid with a tone of 4-letter words. Not once did I wince or think "ugh." Oh, wait, I didn't see ESME (70A: Salinger heroine). That one I could do without. And there's a smattering of crosswordese here and there, but only a smattering, and an inoffensive smattering at that. I don't enjoy doing Roman numeral division in the middle of my solve (66A: CC ÷ XXV => VIII), but with GROOVY (49D: Old-fashioned "Cool!") as one of the crosses on that answer, the enjoyment factor returned.
[XENA!? (33D: TV warrior princess)]
Crosswordese 101: NEVE Campbell (42A: Actress Campbell) — there is exactly one viable crossword NEVE: NEVE Campbell. She was pretty famous, seems like, oh, a decade ago, as a cast member of the FOX series "Party of Five" (1994-2000) and then, making out with Denise Richards, in "Wild Things" (1998). I have no idea what she's been doing lately, though she appears to have been a guest voice on "The Simpsons" just last year.
- 5D: Hostess offerings (CUPCAKES) — clues like this can make a huge difference (relatively speaking) in my solving times. Couldn't just throw it down, even with a couple crosses in place, because "Hostess" was ambiguous (I, of course, though it referred to someone hosting a party ... which, I suppose, it could, if the party in question was a child's birthday party — I think it's safe to say that "Hostess" here is the snack cake company).
- 41D: Book report, e.g. (SYNOPSIS) — again, slowed down by a long Down. Had the SYN- and started thinking "are 'book' and 'report' SYNONYMS of one another ...?" No. Overthinking it. "O" in ORBITS got me back on track.
- 44D: Edith, to Archie (DINGBAT) — aargh. Had the DING- and was surprised when DINGIE wouldn't fit. Not surprisingly, I was confusing my abusive overweight 70s sitcom characters — Mel called Vera "DINGIE" ("DINGY?" "DINGHY?") while Archie called Edith "DINGBAT."
See you Friday,
[Follow Rex Parker on Twitter]
Everything Else — 1A: Life histories, briefly (BIOS); 5A: Atkins diet concern (CARB); 9A: Bogus (FALSE); 14A: Drub in a game (ROUT); 15A: Exploitative type (USER); 16A: Author Zola (EMILE); 17A: Not in favor (ANTI); 18A: Italian tower site (PISA); 19A: Corrective eye surgery (LASIK); 20A: "What?" ("DIDN'T CATCH THAT"); 23A: Nova __ (SCOTIA); 24A: Gentleman's offering on a crowded train, perhaps (SEAT); 25A: Scratch (out), as a living (EKE); 27A: Reason to grab a tissue (SNIFFLE); 32A: "What?" ("EXCUSE ME?"); 37A: Lost color (PALED); 38A: Watered-down (WEAK); 39A: Hangs ten, say (SURFS); 42A: Actress Campbell (NEVE); 43A: Finished (ENDED); 45A: "What?" ("SAY AGAIN?"); 47A: Back-talking (SASSING); 50A: Big bang producer (TNT); 51A: One running in a pusher, for short (NARC); 53A: Circles the Earth (ORBITS); 58A: "What?" ("I BEG YOUR PARDON"); 62A: Toothbrush company (ORAL-B); 63A: Metallurgist's raw materials (ORES); 64A: Choir voice (ALTO); 65A: Modeling wood (BALSA); 66A: CC ÷ XXV (VIII); 67A: Swerve (VEER); 68A: Shoreline irregularity (INLET); 69A: Hankerings (YENS); 70A: Salinger heroine (ESME); 1D: Thin nails (BRADS); 2D: Architectural order (IONIC); 3D: One-up (OUTDO); 4D: Stretch in the service (STINT); 5D: Hostess offerings (CUPCAKES); 6D: Continent crossed by Marco Polo (ASIA); 7D: Score silence symbols (RESTS); 8D: Sources of teen angst, dentally (BRACES); 9D: Sharpie feature (FELT TIP); 10D: Asian nurse (AMAH); 11D: Edelstein of "House" (LISA); 12D: Use a letter opener on (SLIT); 13D: Scared comics cry (EEK); 21D: Connections (TIES); 22D: Solo of "Star Wars" (HAN); 26D: Cousin of an ostrich (EMU); 28D: Vampire tooth (FANG); 29D: Insect in a circus (FLEA); 30D: First name in jeans (LEVI); 31D: First family's home? (EDEN); 32D: Rams' ma'ams (EWES); 33D: TV warrior princess (XENA); 34D: No-goodniks (CADS); 35D: Hawaiian strings (UKES); 36D: Hosp. areas (ERS); 40D: Sprat's taboo (FAT); 41D: Book report, e.g. (SYNOPSIS); 44D: Edith, to Archie (DINGBAT); 46D: Gillette razor brand (ATRA); 48D: Aye's opposite (NAY); 49D: Old-fashioned "Cool!" ("GROOVY!"); 52D: Radium co-discoverer (CURIE); 54D: Atlanta athlete (BRAVE); 55D: Dawdles (IDLES); 56D: Symbol on a pole (TOTEM); 57D: Source of spousal angst, nocturnally (SNORE); 58D: Persia, nowadays (IRAN); 59D: Formal dance (BALL); 60D: Apart from this (ELSE); 61D: Jockey strap (REIN); 62D: Kimono sash (OBI).