On a reality-heavy night, Fox easily led the primetime ratings race Wednesday with a two-hour installment of “So You Think You Can Dance,” while ABC was solid with “Wipeout” but faltered some with the return of “I Survived a Japanese Gameshow.”

According to preliminary nationals from Nielsen, “So You Think You Can Dance” (3.0 rating/9 share in adults 18-49, 8.4 million viewers overall) grew with each half-hour to comfortably win its 8-10 p.m. timeslot. It was down a bit week to week, as the show typically tends to dip as the original field of 20 contestants is narrowed to a more manageable number.

At ABC, “Wipeout” (2.6/9 in 18-49, 8.0 million viewers overall) was in line with its performance in the hour last week, placing a solid second to “Dance” in all categories. The net then dipped from there with the second-season premiere of “I Survived a Japanese Gameshow” (2.1/6 in 18-49, 5.4 million viewers overall), which placed second in its timeslot, and finished third among the broadcasters at 10 o’clock with the finale of drama “The Unsuals” (1.3/4 in 18-49, 3.9 million viewers overall).

NBC’s “I’m a Celebrity, Get Me Out of Here” (1.5/5 in 18-49, 4.2 million viewers overall) posted its lowest score to date as it nears its finale, and the net filled out the night with repeats of “Law & Order” at 9 p.m. (1.0/3 in 18-49, 3.8 million viewers overall) and 10 p.m. (1.4/4 in 18-49, 4.9 million viewers overall). The Peacock should fare better on the night beginning next week with the return of “America’s Got Talent” and the launch of drama “The Philanthropist.”

CBS started slowly with repeat comedies “The New Adventures of Old Christine” (1.1/4 in 18-49, 4.3 million viewers overall) and “Gary Unmarried” (1.2/4 in 18-49, 4.4 million viewers overall) before faring better with encores of crime dramas “Criminal Minds” (1.9/6 in 18-49, 8.1 million viewers overall) and “CSI: NY” (1.6/5 in 18-49, 7.9 million viewers overall).

Preliminary 18-49 averages for the night: Fox, 3.0/9; ABC, 2.0/6; CBS, 1.5/5; Univision, 1.4/4; NBC, 1.3/4; CW, 0.4/1.

In total viewers: Fox, 8.4 million; CBS, 6.8 million; ABC, 5.8 million; NBC, 4.3 million; Univision, 3.7 million; CW, 1.0 million.