Katy Perry's 'Part Of Me' Movie Disappoints At US Box Office

Katy Perry's concert movie 'Part Of Me' is suffering from all the stiff competition at the US Box Office this weekend, including 'The Amazing Spider-Man'.

The documentary film, following Perry from before her fame days up to the conclusion of her Teenage Dream world tour, opened on Thursday with a modest $3.1 million gross, according to The Hollywood Reporter.

Experts expect its total for the weekend will finish in the low-to-mid teens millions-wise - not too bad considering it only cost $12 million to make, but only enough to score an underwhelming chart placement of No. 5.

By comparison, Justin Bieber's 'Never Say Never' managed $29.4 million in its opening weekend last year, and 'Hannah Montana: Best of Both Worlds Concert Tour' collected $31.1 million in 2008. Both of those, however, were released outside of the competitive summer period.

At the top of the pile is 'The Amazing Spider-Man', which took $35 million on its opening day (Tuesday) and is expected to have bagged north of $130 million by the end of today's business.

'Part Of Me's UK figures will be announced in the middle of next week.

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