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You need to introduce you characters that's a given but do you need to introduce them to the readers as a separate exercise, there I'm not so sure. It's going to read a little flashback-ish but if ...
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Source: https://writers.stackexchange.com/a/32813 License name: CC BY-SA 3.0 License URL: https://creativecommons.org/licenses/by-sa/3.0/
#2: Initial revision
You need to introduce you characters that's a given but do you need to introduce them to the readers as a separate exercise, there I'm not so sure. It's going to read a little flashback-ish but if you present them to each other and they tell their stories of how they got caught up in this whole saga to each other, preferably with action scene interruptions you can introduce them separately and together at the same time and reduce the information burden on the reader to something manageable.