“Knock Knock”
“Who’s there?”
Very few viewers.

Fox’s “Knock Knock Live” — hosted by Ryan Seacrest — debuted to just a 0.5 18-49 demo rating and 1.7 million total viewers on Tuesday. As a result, Fox finished beneath both Spanish-language networks in the main demo, tying for fifth with ABC, which aired just one original program. That show was “Extreme Weight Loss,” which fell 25 percent from last week in ratings.

Meanwhile, NBC finished first with “America’s Got Talent” and “Hollywood Game Night.” Telemundo won the bronze in the key demo, but didn’t fare as well in overall audience size.

NBC was first in ratings with a 1.9 rating/7 share in the advertiser-coveted 18-49 demographic and in total viewers with an average of 8.5 million, according to preliminary numbers. At 8 p.m., “AGT” scored a 2.3/9 and 10.3 million viewers. At 10, “Hollywood Game Night” posted a 1.3/5 and 4.9 million viewers.

CBS was second in ratings with a 0.9/3 and in viewers with 6.5 million. Between reruns, “Zoo” at 9 received a 1.0/4 and 6.6 million viewers.

Telemundo was third in ratings with a 0.8/3, but sixth in viewers with 1.7 million.

Univision was fourth in ratings with a 0.7/3 and fifth in viewers with 1.9 million.

ABC and Fox tied for fifth in ratings, both with a 0.6/2. ABC was third in total viewers with 2.3 million; Fox was fourth with 2.1 million.

For ABC, following repeats, “Extreme Weight Loss” at 9 had a 0.6/2 and 2.3 million viewers.

For Fox, a special “So You Think You Can Dance” retrospective at 8 got a 0.7/3 and 2.4 million viewers. “Knock Knock Live” was at 9, with a 2 share.

The CW was seventh in ratings with a 0.3/1 and in viewers with 1.2 million, airing reruns.