Your barcode 012569821255 combines two films (serials) together which should probably be separate films in a boxed set. The title on the cover and spine is Superman: The Theatrical Serials Collection. There are 2 discs per film. You now have all the chapters combined as well. The chapters from the first movie are your 1-15 as is. For the second movie they should be renumbered 1-15 starting with your number 16. Cast and credits are also combined. Should you want to change this, the two movies are:
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