Daniel Radcliffe goes topless in Weird Al Yankovic trailer

Watch: First look at Daniel Radcliffe as Weird Al Yankovic

Daniel Radcliffe promises he is "full of surprises" as he appears topless in the first trailer for his new movie Weird: The Al Yankovic Story.

The Harry Potter actor stars as comedy singer Weird Al Yankovic in the biopic - set to air on streaming service Roku this autumn.

Radcliffe, 32, dances shirtless on stage in front of a screaming crowd to the tune of Madonna's hit Like A Virgin and tells them "I hope you guys are ready for this".

Read more: Daniel Radcliffe says playing Weird Al Yankovic is 'huge responsibility'

He then brandishes an accordion and bursts into a rendition of Yankovic's hit parody Like A Surgeon, strutting topless on stage as he swigs from a bottle of whiskey.

Radcliffe dons a curly wig, large wire-rimmed glasses and a bushy moustache to become Weird Al for the film.

The British actor - who rose to fame playing boy wizard Harry Potter from the age of 11 in the hit film franchise - shows off his dance moves and fight skills in the one minute comedy trailer.

The teaser ends with him announcing: "What can I say, I'm full of surprises."

Comedy singer Weird Al and Daniel Radcliffe
Daniel Radcliffe appears topless in the new trailer for Weird: The Al Yankovic Story. (Getty Images)

Last year, Radcliffe admitted to being "intensely embarrassed" by some of his acting in the early years of his career on the Harry Potter films where he first found fame.

Yankovic, 62, is the biggest-selling comedy recording artist of all time and has won five Grammy awards.

His 2014 release Mandatory Fun was the first comedy album in history to debut at number one on US music chart Billboard’s Top 200.

Daniel Radcliffe in Harry Potter and the Philosopher's Stone. (Warner Bros)
Daniel Radcliffe in Harry Potter and the Philosopher's Stone. (Warner Bros)

Songs have included Michael Jackson Beat It parody Eat It, and Whole Lotta Lunch, a parody of Led Zeppelin's Whole Lotta Love.

Celebrities including Jack Black, Seth Green and Donny Osmond have appeared in his music videos.

Production on the biopic, which will chart his rise to fame creating spoof versions of popular songs, began in Los Angeles in early February.

Read more: Daniel Radcliffe is 'intensely embarrassed' by his early Harry Potter acting

Yankovic previously said he was "thrilled" to be portrayed by Radcliffe and joked that the film would be, "the role future generations will remember him for."

Watch: Daniel Radcliffe and Sandra Bullock discuss working with naked Channing Tatum