Puzzle

 ACROSS

  1 *"KA-BLAM!"

  5 *"Cheers" for the other team

  9 *Big cheese

 13 Suit in King Arthur's court?

 15 Feature of "this clue ... ue ... ue ..."

 16 Minstrel's instrument

 17 Lerner's partner

 18 "Pay ___ mind!"

 19 School founded by King Henry VI

 20 19-Across' country: Abbr.

 21 Actor Sal

 23 Already cut, as logs

 24 20th-century example of the starred word ladder's start

 28 Home of MA and PA

 29 Apt first name for a retirement planner

 30 Lowest Monopoly roll

 31 Taunts

 34 Noted fabulist

 36 Meat paired with Swiss

 37 Sacagawea dollars' equivalents

 38 Exclaims

 39 "Joker" or "The Lion King"

 40 Gomez Addams' cousin

 41 Coeur d'___

 42 Honorific

 43 Still in the package

 44 Like crunchy carrots

 45 Identify on Facebook

 46 20th-century example of the word ladder's end

 53 Fish-eye, for one

 54 Bedtime story?

 55 Southeast Asian language

 56 Provide money for

 57 Feathery wraps

 58 Absolutely necessary thing

 60 Together, musically

 61 "My treat!"

 62 Skin care brand

 63 *First lady Truman

 64 *Top, or tops

 65 *It might be placed on a pedestal

DOWN

  1 Hay machine

  2 Maine college town

  3 Horseshoelike Greek letter

  4 Cut, as grass

  5 Existence

  6 Black pawns in chess, e.g.

  7 Response to a good explanation

  8 Great Lakes' ___ Canals

  9 Sheep sound

 10 "Spill the beans!"

 11 Deliberately delay

 12 Former Pres. Obama, once

 14 Careless

 22 With 23-Down, almost instantly

 23 See 22-Down

 25 Bitterly regrets

 26 Busy boy on Valentine's Day

 27 Amiens' river

 31 Departing

 32 Theater break

 33 "Don't tell anyone this ..."

 34 "Anything else?"

 35 German article

 38 Attired

 39 Newton fruits

 41 Performing ___

 42 Western discoverer of New Zealand (MANTAS anagram)

 45 Caddy contents

 47 South American range

 48 Royal baby buggies

 49 Change, as a password

 50 Candy heart sentiment

 51 Welcome desert sights (and sites)

 52 Absent from

 56 ___ Four

 57 Short haircut

 59 1997 sci-fi comedy, for short

Solution