While being known as the Master of Horror, what many readers love about Stephen King is not how scary his books are but how he writes characters whose lives and stories matter. A great place to explore how King creates compelling and memorable characters is the Stephen King Cast.
The podcast explore and reviews each King book and often covers the movie adaptation as well in a follow-up episode.
I'm tempted to recommend two episodes about The Dead Zone because that's my personal favorite of all of King's novels. But an even better episode for learning about creating compelling characters is The Shining movie episode. (If you have time, listen to the book review episode as well.)
In The Shining movie review, the host of the Stephen King Cast compares the book and the movie. This comparison includes rating each major character in the book versus the same character in the movie, voting on which works better, and giving specific reasons why.
What's so valuable is that the Stephen King Cast host speaks as a reader and a viewer rather than as an author, as in the end it's readers who decide what stories are most compelling.
Until Sunday, when I'll talk about creating conflict through characters with competing goals.
P.S. If you're struggling with developing characters, you can also check out Writing As A Second Career's Free Character Creation Tip Sheet for questions to ask yourself that might help.