A check for $50,000 delivered by Justin Bieber can go a long way for a financially struggling family with a child with Down Syndrome Yes, but that, a belated quinceañera surprise and other acts of kindness and money from the Canadian superstar wasn’t enough to improve the fortunes of Knock Knock Live (0.5/2). The second week of the Ryan Seacrest hosted unscripted surprise show was even with the fast nationals of its debut and down 17% among adults 18-49 from its July 21 final numbers. Added up against everything else on TV last night, KKL was the lowest rated original of Tuesday’s primetime. Also telling is that the show saw an 11% decline in total viewers to just 1.56 million. Or to put it another way, Knock Knock Live was the second least watched show overall last night with 320,000 more viewers than a Flash repeat on The CW. Unlike its July 21 debut, which saw a So You Think You Can Dance 10th anniversary special as the lead-in, KKL had a new Are You Smarter Than A 5th Grader (0.6/3) preceding it. The Jeff Foxworthy hosted show was even with its last original of July 7.

Despite some hiccups of their own, the real winner of primetime was NBC with America’s Got Talent (2.1/8) and Hollywood Game Night (1.3/4) taking the first and second ratings spots of the night. The most watched show of the night with an audience of 10.20 million, AGT slipped 9% from last week to hit a season low in preliminary numbers. Don’t get too hung up on that, the competition show commonly sees an adjustment in later numbers. Hollywood Game Night was even with its July 21 show. Overall, NBC easily took the night with a 1.8/7 rating among the demo and viewership of 8.4 million.

ABC and CBS only had one original each on Tuesday night but both saw double-digit rises. Up and down like a dieter, Extreme Weight Loss (0.7/2) put on 17% among the 18-49s after last week’s series low – which had seen a drop of 25% from its July 14 show. CBS’ Zoo (1.2/4) was up 20% among adults 18-49 and 6% among overall viewers to 7.07 million watching.

The CW was all encores.