There may have been no signature moment at this year's MTV Video Music Awards, but there was a signature sound: the screams of teenage girls wild about One Direction.

It stopped just short of a British invasion, but the hunky teens in the boy band won three awards on the Los Angeles show and barged in on Rihanna's party.

Rihanna kicked off things with a spicy performance to open the show, then ended it by taking the show's top honour, video of the year, for her steamy hit We Found Love.

She wore a figure-hugging, elegant scoop-backed white dress before changing into a flowing red outfit for her medley of new single Cockiness (I Love It) with rapper A$AP Rocky and We Found Love.

The camera returned to the pop star often - except when it was on One Direction, which provided the night's most screamed-over performance. The band won best pop video, best new artist and most share-worthy video.

"We've grown up watching this show and to even be here is an honour," Niall Horan said from the stage.

The quintet seemed stunned as fans screamed upon announcement of their win. The group performed later, rising to a stairwell surrounded by screaming, reaching female fans on an elevated platform and bringing most attendees to their feet.

"This has been unbelievable," Harry Styles said backstage. "This was our favourite performance we've ever done. For us to be here in the first place is amazing, and to perform and win a Moonman is amazing."

Chris Brown pulled off something of an upset in the best male video category. Rihanna's former boyfriend won for his self-directed video Turn Up The Music, beating out several top stars, including Drake, who tied Rihanna for most nominations with five. Brown also won for best cinematography.