Star Trek's "Captain Kirk", William Shatner.
Star Trek Deep Space Nine's "Odo" Rene Auberjonois.
Star Trek Voyager's "Seven of Nine" Jeri Ryan.
William Shater and Rene Auberjonois worked together on Star Trek VI: The Undiscovered Country before starring together on Boston Legal. However, neither Bill nor Rene worked with Jeri Ryan in a Trek project. It is unclear if Rene and Jeri will be sharing scenes, although it does look like Bill and Jeri will.
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