Fast National ratings for Wednesday, June 18, 2014.

A large, but slightly unexplained, bump for "So You Think You Can Dance" helped FOX dominate Wednesday primetime in young viewers and finish a close second to CBS' procedural repeats overall.

Also getting an unexplained week-to-week boost was ABC's "Motive," the only other original on a repeat-filled night.

If you're curious, "Motive" was up 15 percent overall and 25 percent in the key demo, while "So You Think You Can Dance" rose 31 percent in the key demo and 20 percent overall.

On to the numbers...

Among adults 18-49, FOX averaged a 1.7 rating for Wednesday night, far ahead of the 1.0 rating posted by ABC, CBS and NBC in the key demographic. The CW averaged a 0.3 key demo rating for the night.

Overall, though, CBS averaged an estimated 5.5 million viewers and a 3.7 rating/7 share for Wednesday primetime, edging out FOX's 5.27 million viewers and 3.3/6. [FOX eked out a slim overall advantage for the two shared primetime hours.] ABC was third with 4.21 million viewers and a 2.7/5, topping NBC's 3.9 million and 2.6/5. The CW averaged 977,000 viewers and a 0.7/1 for the night.

8 p.m. - CBS started primetime in first overall with just over 5.04 million viewers for a "Hawaii Five-0" repeat, which finished fourth with a 0.8 rating among adults 18-49. FOX's "So You Think You Can Dance" was a close second with just under 5.04 million viewers and won the hour with a 1.6 key demo rating. NBC's "Law & Order: Special Victims Unit" repeat was third with 4.26 million viewers and second with a 1.1 key demo rating, topping the 4.195 million viewers and 0.9 key demo rating for ABC's repeats of "The Middle" and "The Goldbergs." The CW's "Arrow" repeat averaged 970,000 viewers and a 0.3 key demo rating.

9 p.m. - FOX's "So You Think You Can Dance" moved up to first in the 9 p.m. hour with 5.5 million viewers and a 1.7 rating among adults 18-49. CBS' "Criminal Minds" repeat was second with 5.47 million viewers, but stayed fourth with a 1.0 key demo rating. Another "Law & Order: Special Victims Unit" repeat averaged 4.47 million viewers and a 1.2 key demo rating for NBC,  compared to the 3.75 million viewers and 1.2 key demo rating for repeats of "Modern Family" and "The Goldbergs" on ABC. The CW's "The 100" repeat averaged 983,000 viewers and a 0.3 key demo rating.

10 p.m. - CBS moved back into first in the 10 p.m. hour with 5.99 million viewers for a "CSI: Crime Scene Investigation" repeat, which also tied for the lead with a 1.0 rating among adults 18-49. ABC's "Motive" was second with 4.67 million viewers and also did a 1.0 key demo rating. NBC's "Chicago PD" repeat averaged 2.96 million viewers and a 0.8 key demo rating.

All ratings information comes from preliminary Fast National Nielsen data, which includes live and same-day DVR viewing. All numbers are subject to change.