Melissa McCarthy notched her first No. 1 weekend box-office debut as a leading lady with the $30 million opening of her espionage comedy “Spy.” According to studio estimates Sunday, McCarthy’s latest film with director Paul Feig bested a varied field of action, horror and a resurrected HBO series. Last week’s top film, “San Andreas,” the disaster movie starring Dwayne Johnson, slid to second place with $26.4 million.
