TV Ratings: 'Knock Knock Live' Premieres As Summer's Latest Unscripted Slipup

Knock Knock Ryan Seacrest - H 2015

Knock Knock Ryan Seacrest - H 2015

Who's there? Apparently not too many viewers. Knock, Knock Live premiered on Tuesday night, and Fox's latest play for summer unscripted success fell flat.

The one-hour show, top-lined by Ryan Seacrest, averaged a mere 0.5 rating among adults 18-49 and just 1.7 million viewers. It joins Boom!, Are You Smarter Than a 5th Grader and (to a lesser extent) Bullseye in the bowl of recent reality forays that couldn't move the dial. Its lead-in, a retrospective special for the 10-year anniversary of So You Think You Can Dance, nabbed a 0.7 rating in the key demo.

There have been a barrage of new unscripted series across the Big Four this summer, more than in recent years, and thus far ABC's Celebrity Family Feud is the only one to break through in a formidable way.

Elsewhere Tuesday night, NBC led with steady episodes of America's Got Talent (2.3 adults) and Hollywood Game Night (1.4 adults).

CBS had a new Zoo, even with a 1.0 rating with adults 18-49, while ABC had a steady Extreme Weight Loss (0.6 adults).