The mirror crack'd from side to side : level 4

The quaint village of St. Mary Mead has been glamorized by screen queen Marina Gregg, who's taken up residence in preparation for her comeback. But when a local fan is poisoned, Marina finds herself starring in a real-life mystery--supported with scene-stealing aplomb by Miss Jane Marple, who suspects that the lethal cocktail was intended for someone else. But who? If it was meant for Marina, then why? And before the final fade-out, who else from St. Mary Mead's cast of seemingly innocent characters is going to be eliminated?