1: PDA entry

5: Black tie affairs

10: Nutmeg covering

14: New Mexico necktie

15: Slow to act

16: Give the slip to

17: Holmes mantra, and a hint to this puzzle's theme

19: Symbol of stubbornness

20: Grill

21: School term

23: Blubber

26: Churchill's title

27: 'Boston Public' figure

34: Piece of strategy

36: Historical period

37: Oil source

38: Bird with an eerie call

39: African snake

42: Up to the task

43: Related to vision

45: Eyeball

46: Take a chance

47: Hazarding a guess: critic who studies Hitchcock?

51: Choose

52: Spot

53: Fragments

58: Saw

63: Golfer Irwin

64: Repeated

67: Sesame starter?

68: Moving about

69: Louisiana politician Huey

70: Nursing need

71: Swindled

72: Olympic weapon

1: Assist larcenously

2: Game on horseback

3: “Not guilty,” e.g.

4: Hanks and Cruise

5: Beefeater, e.g.

6: Aardvark's tidbit

7: Meadows

8: Scene from 'Cops,' e.g.

9: Get in the way of

10: Help for the hapless

11: 100-0, e.g.

12: Sea spot

13: Dirty look

18: Inscribe with acid

22: Segments of history

24: Wander about

25: Meditation method

27: Like many chimneys

28: One with a critical attitude

29: Bar wedge

30: Scorches

31: Riding attire

32: Silly pair?

33: Be a stinker

34: Alka-Seltzer jingle starter

35: Uses an ax

40: Scottish hillside

41: In a competent way

44: Rough waters

48: Verdi creations

49: Bear witness

50: Cornerstone datum

53: Whiskey measure

54: Back of the neck

55: Some intestinal divisions

56: Cooped (up)

57: In ___ (unmoved)

59: Either of the racing Earnhardts

60: Capping

61: Kind of pool

62: Upper hand

65: Tenth wedding anniversary gift

66: Energy unit