The best, worst and weirdest moments at the 2016 Billboard Music Awards

The Billboard Music Awards kicked off in Las Vegas on Sunday night, where some of the biggest names in music came out to deliver some powerful, emotional and wildly entertaining performances. But not every star could shine bright, which left viewers with some almost inexplicably strange moments.

From Celine Dion proving the show must go on to Ciara proving that maybe her co-host, Ludacris, should have handled more of the emcee duties, here are some of the best, worst and weirdest moments from the 2016 Billboard Music Awards.

MORE: 2016 Billboard Music Awards -- The Complete Winners List

THE BEST

1. Celine Dion Rules the Stage

In her first televised performance since the death of her husband, Rene Angelil, Dion was honored with the Icon Award and delivered a powerful, fierce rendition of Queen's single "The Show Must Go On."

The singer's bold delivery -- as well as her tearful acceptance speech -- solidified her position as the night's biggest highlight.

WATCH: Celine Dion on Emotional BBMAs Honor and Son's Surprise

2. Kesha's Stunning Cover

Rocking a conservative country western ensemble, Kesha delivered an emotionally charged cover of Bob Dylan's 1964 classic "It Ain't Me, Babe," accompanied by Ben Folds on piano and violinist Rob Moose. The touching performance -- which almost didn't even happen -- elicited a standing ovation from the audience.

3. Rihanna Shows Her True Vocal Talent

Rihanna's stripped-down vocals and raw, emotional delivery of her ballad "Love on the Brain," stood out among many of the more explosive, flashy performances of the night. And her seafoam green, fur-lined black pantsuit would have won her a spot on the best list by itself.

PHOTOS: 2016 Billboard Music Awards Red Carpet Arrivals

4. The End of Britney Spears' Performance

Spears kicked off the awards show and, after a very rocky start, the "Toxic" singer got into her stride, delivering what was basically the song list from her Las Vegas residency show, but in medley form. However, the singer showed off the results of her hard work, flaunting her flawless physique across the stage and looking the best she's looked in years.

5. Fans Losing Their Minds Over Justin Bieber