Episode 4 of America's Got Talent 2013 will feature opera singers, dancing kids, jugglers and what looks like a dog doing magic tricks, according to NBC's preview.

At the beginning of the preview, the narrator says, "The summer's no. 1 show brings you the hottest young talent." After a group of dancing boys finish their act, judge Howie Mandel asks them, "Do you guys get a lot of girls?" to which one of them replies "We're Italians" while nodding his head.

The most highlighted portion of the preview, however, is a trio of opera singers who had supposedly only met "a few days ago." When they begin to sing, Mandel and fellow judge Heidi Klum look on in shock, prompting Mandel to say, "You guys are phenomenal."

View the 30-second promo here:

As for last week's acts, many clips were uploaded to YouTube and it has been revealed which ones were more popular with the public. Coming in at almost 5.5 million hits, martial arts-style dancer Kenichi Ebina has the most hits by far as of Tuesday morning. He has the most views of any act in competition this year so far, with only Special Head as their other act with over a million views.

At a distance second is Darby, the 5-year-old cheerleader, who has close to 250,000 hits. Right behind Darby is Omega Force, whose display of brute strength got them about 230,000 hits, and Red Panda, whose ability to balance bowls on her head while on a unicycle got her about 225,000 hits.

Stats like this may be good indicators of which acts America will be interested in voting for in the coming rounds. 

America's Got Talent will air its two-hour fourth episode of the season Tuesday night at 9 p.m. on NBC. Watch the third episode of America's Got Talent 2013 in its entirety here: