Step Brothers crowns box office

Will Ferrell (l) and John C Reilly team up for Step Brothers

Will Ferrell's latest comic caper Step Brothers has made its debut in the UK and Ireland box office at number one.

The film, which tells the tale of two adult brothers brought together by an unexpected marriage, was followed by Mamma Mia! at number two.

Horror flick The Strangers and sci-fi film Babylon AD were the other new entries at numbers three and seven.

Last week's chart-topper, Hellboy II: The Golden Army, fell to number four, with The Dark Knight at five.

UK/ IRELAND TOP FIVE 1 Step Brothers - £1.68m 2 Mamma Mia! - £1.54m 3 The Strangers - £1.25m 4 Hellboy II: The Golden Army - £1.02m 5 The Dark Knight - £908,618 Source: Screen International

Mamma Mia! has taken £53m at UK cinemas to date and remains the highest-grossing film in the top 10 after eight weeks of release.

It remains ahead of The Dark Knight's total takings, which stand at £45.7m after six weeks in cinemas.

Box office analysts Screen International initially reported that Mamma Mia! had made a return to the top spot before revising their final figures.