Like Cheryl said, Fandango is very easy to do what you want to do.
I reserved seats for "Toy Story 4", when it was out over the summer, but I just went there and they show you the screen and ask you to pick the seats that you want. I do live about 2 minutes from the theater though. So if you don't live close, you may want to give them a call and ask. Otherwise, just go up there and tell them that you want to reserve the seats and they should show you the screen and then you can pick out the 15 seats you want. I think you can also go online and reserve them with your credit card. It would be fandango.com and just fine the Columbia Snowden River, and then you can just order them with a credit card.
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