Sandra Bullock's forthcoming action-adventure rom-com The Lost City has some spectacular stunts and even more exciting cameos — and the actress is opening up about how some of the movie's most memorable moments came to be.Bullock and co-star Daniel Radcliffe recently sat down with ET's Cassie DiLaura, and they reflected on some of the movie's most exciting scenes — including a daring rescue by Brad Pitt that featured an enormous explosion.«We only did that shot in one take!» Bullock revealed. «We didn't know how big the explosion was gonna be. It's all about preparation, preparation, preparation and then a whole lot of luck.»Bullock stars in the film as Loretta Sage, a reclusive romance-adventure author who's spent her career writing about exotic places.