While it is still needs a title, Nancy Meyers' upcoming film boasts an unbelievable ensemble of talent -- including Meryl Streep, Alec Baldwin, and Steve Martin. Only ET is on the set of the untitled film, where the stars reveal some of the plot details and take a stab at naming the romantic comedy! It’s a rare look at a Meryl movie as it shoots, and ET has learned the Oscar-wining actress plays a baker in the film, Alec plays her ex, and Steve is the architect designing Meryl's character's new house — and the three are in a love triangle.    The film is being helmed by writer/director Nancy Meyers, who has worked her magic in such memorable flicks as 'Father of the Bride,' 'The Parent Trap,' 'What Women Want,' 'The Holiday' and 'Something's Gotta Give.'