Almost every time you have some kind of "free" ticket you will have to take it to the box office. You can go early; as soon as they post the schedule for the week, head over to the theater and get what you need. For a short line be sure to go about 30 minutes after the last movie starts for that timeframe.
Have to buy tickets in person to use "free" ticket coupon. And be prepared for an up charge, as they no longer offer standard seating.
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