Theme: The game is afoot! - "The Transient Associate Adventure" The various Dr. Watson portrayers.
Let's start with the author.
15D. With 48-Down, 1-/69-Across creator Arthur : CONAN.
48D. See 15-Down : DOYLE. And then:
1A. With 69-Across, subject of this puzzle : DOCTOR
69A. See 1-Across : WATSON ...and our cast.
7A. Portrayer of 1-/69-Across in "Sherlock Holmes" (2009) : JUDE LAW
38A. Portrayer of 1-/69-Across in the BBC's "Sherlock" : MARTIN FREEMAN
68A. Portrayer of 1-/69-Across in CBS' "Elementary" : LUCY LIU
Argyle here. Mike's puzzle two years ago was a pip. Link Scroll down to the grid to see the genius of that puzzle. Some fill and theme entries are the same length while four verticals are only bested by the central theme for length. It isn't a detriment to the solve. It has a fresh feel to it and I liked it.
14. Not straying from the subject : ON TOPIC
16. Satan : EVIL ONE
17. "The Diary of Anne Frank" police : GESTAPO
18. Muscle-to-bone connectors : TENDONS
19. Audio jack label : MIC
20. Took charge of : RAN
21. Wise folk : SAGES
22. Rewrite for the screen : ADAPT
24. Set a price of : ASK
26. Northern California town that once had a palindromic bakery : YREKA. Yreka Bakery is no longer in business.
29. Mentally sound : SANE
30. Live, in the studio : ON AIR
32. Kool-Aid instruction : STIR
33. Ostrich kin : EMU
35. "I __ Fine": Beatles hit : FEEL
37. Antlered beast : ELK
42. World games org. : IOC
43. A bit open : AJAR
44. "C'est la __" : VIE
45. Cry for seconds : MORE
47. Battery end : ANODE
49. Rise dramatically : SOAR
53. Sticking point : PRONG
55. Game won by discarding all your cards : UNO
56. Iditarod jacket : PARKA
57. Wood finish : STAIN
59. DKNY rival : YSL
61. Press __ : KIT
62. Dannon yogurt brand : ACTIVIA
64. Natives of Tibet's capital : LHASANS
66. Unlisted candidate : WRITE-IN
67. Erode, as savings : EAT INTO
1. Rigid beliefs : DOGMAs
2. Tableware company named for a New York town : ONEIDA. NNE of Elmira.
3. ER diagnostic tool : CT SCAN
4. Day care attendee : TOT
5. Eyeball-bending gallery display : OP ART
6. TV host Kelly : RIPA
7. Watercraft rider : JET SKIER
8. Eye layer containing the iris : UVEA
9. Dull-colored : DINGY
10. Senior officials : ELDERS
11. It's brewed in infusers : LOOSE TEA
12. Political writer Coulter : ANN
13. Director Anderson : WES. Nominated for the Academy Award for Best Original Screenplay for The Royal Tenenbaums, Moonrise Kingdom and The Grand Budapest Hotel, as well as for Best Animated Feature for Fantastic Mr. Fox.
23. Jury member : PEER
25. Paella spice : SAFFRON
27. Ceramics oven : KILN
28. Noah's flood insurance : ARK
30. Message-spelling board : OUIJA
31. Superman player Christopher : REEVE
34. Former Boston commuter org. : MTA. (Metropolitan Transit Authority)
36. "Welcome to Hawaii" gift : LEI
38. Secure in a harbor : MOOR
39. Quotation puzzle : ACROSTIC
40. Mork's sign-off : NANU NANU. 50D. Mork's people : ORKANS
41. Southwestern tableland : MESA
42. Tough kid to handle : IMP
46. Thing : ENTITY
51. Quite like : AKIN TO
52. Gives away to the cops : RATS ON
54. "Sold!" punctuator : GAVEL
56. Spanish silver : PLATA. Remember the state motto, "Oro y plata"?
58. Four, on some sundials : IIII
60. "Major Barbara" playwright : SHAW. (George Bernard Shaw)
62. Hole-making tool : AWL
63. French wine word : CRU. It means vineyard; we had it last month.
65. "Grab a chair" : "SIT"