1. Retired boomers?
2. Dance trio?
3. One role for a center
4. Not according to Mr. Spock
5. Typewriter roller
6. Chicago-based magazine
7. Actress Helgenberger of "CSI"
8. __ nose
9. "Not likely!"
10. Like some people resisting arrest
11. Rwandan people
12. Rub off the board
13. First name in 2000s talk
14. Skid's cause, maybe
20. "__ My Heart in San Francisco"
23. Anakin Skywalker, ultimately
24. Something to try
25. Simon of Duran Duran
28. Awards for romances
30. ***UNCLUED***
31. Placed on, as the board
32. Worry
33. McKern and McCarey
36. "And their lies caused them __" (Amos 2:4)
39. Heckart and Brennan
43. Castle with many steps
45. One "in distress"
46. Ices, maybe
47. WWII pilot Paul Tibbets's mother
48. Scamper for six
49. Carried
50. Stressed
52. __ Squad (Best Buys crew)
53. Metallica drummer Ulrich
55. Govt. ID issuer