Citizen Kane, a 1941 movie by Orson Welles
Starring Orson Welles and Joseph Cotton. Also notice Agnes Moorehead as his mother Mary Kane.
A very wealthy newspaper publisher Charles Foster Kane dies and his last word on his deathbed is "Rosebud". A search begins, interviewing everyone who ever knew him, to create a full biography of him in an attempt to find out, to what "Rosebud" refers.
Buy the book Citizen Kane on Amazon
Buy the Making of Citizen Kane on Amazon