They are fan created films, but they have Walter Koenig (Chekov) guest star, and supposedly are pertty well done. The episodes are a continuation of the Original Star Trek Series, this is not a new crew, they play Kirk, Spock and the rest.
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The acting can be a little shaky at times, but the effects are great and the stories are pretty darn good. Some of them are even written by the original series writers!