Puzzle

 ACROSS



  1 Littleneck mollusk

  5 "Body Party" vocalist

 10 Virtually closed

 14 Inflated publicity

 15 Venomous viper

 16 Genre related to soul and R&B

 17 "Sports-Center" channel

 18 "Rocketman" instrument

 19 2012 Ben Affleck thriller

 20 Recollection of a weak poker hand?

 23 What some sloths do for 20 hours a day

 24 Spot in Congress

 25 Stubbed digit

 28 Truth alternative

 31 Infield covers

 33 Anatomical pouch

 36 Successful freelance writer's drawerful?

 40 Illegally off base, for short

 42 Shrine to "remember"

 43 ___ Zor-El (Supergirl)

 44 Security hardware at Dracula's castle?

 47 Produce, as an egg

 48 Faucet repair gasket

 49 Narrow valley

 51 Kind of room or center

 52 Diamond Head locale

 56 Apres-ski setting

 60 People who prefer to do crosswords on their computers?

 64 Shrunken Asian sea

 66 Apt fabric for a chair cover?

 67 "Law & Order: SVU" star

 68 "Horrors!"

 69 Like a ewe

 70 One of Canada's First Nations

 71 2000s TV show set on an island

 72 Secret looks

 73 Bronte's Jane

DOWN

  1 Culinary VIPs

  2 Disinfectant brand

  3 Pie fruit

  4 Patched up

  5 ___ Crunch

  6 "Gotcha, man!"

  7 First White House occupant

  8 Zellweger in movies

  9 Donut shop allure

 10 In the distance

 11 Event for some litigants

 12 Taiwanese director Lee

 13 "Cimarron" studio

 21 Hoppy pints, briefly

 22 Inflatable pilot in "Airplane!"

 26 "Rigoletto," for one

 27 Common App component

 29 Loud crowd sound

 30 French fashion magazine

 32 Biblical craft

 33 Take pleasure in

 34 In the loop

 35 Bad choice for a master's thesis font

 37 Small amount

 38 Urban blanket

 39 Cost to cross

 41 Clinic pro

 45 Frankenstein's helper

 46 Swiss folk hero William

 50 Beginner

 53 Ancient fabulist

 54 Hurl

 55 Set free

 57 Condemn

 58 Germaine who wrote "The Female Eunuch"

 59 Lauder of note

 61 Coagulate

 62 Approach the bottom

 63 Tip jar fillers

 64 Classic ISP ... or, with = properly placed, this puzzle's theme

 65 P, to Persephone \

Solution