Anne Fletcher's charming romantic comedy "The Proposal" debuted at the No. 1 spot at the North American box office with an estimated $12.4 million in ticket sales from 3,056 locations.

Starring Sandra Bullock and Ryan Reynolds, the film follows an overbearing book editor who blackmails her assistant into marrying her after she faces deportation to Canada. Betty White co-stars.

At No. 2, Harold Ramis' mediocre comedy "Year One" took home $8.5 million from ticket sales at 3,022 locations. Jack Back and Michael Cera star as two cavemen who are banished from their tribe and embark on their own big adventure.

Last week's box office champion "The Hangover" slipped to third place Friday, scoring $8.4 million. The Todd Phillips-directed comedy brought its domestic gross to a solid $134.5 million.

Following at No. 4 was Pixar's "Up," which collected $6.2 million for a total of $208.8 million. Tony Scott's "The Taking of Pelham 1 2 3" finished fifth, pulling a daily gross of only $3.2 million for a cumulative gross of $35.2 million.

Source: Box Office Mojo (www.boxofficemojo.com)