The main cast for CBS All Access' Star Trek series featuring the return of Sir Patrick Stewart reprising his role as Jean-Luc Picard continues to grow, with three new series regulars added.

Alison Pill, Harry Treadaway and Isa Briones have all been cast in the upcoming series in currently undisclosed roles as pre-production on the show continues.

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Pill is perhaps best known for roles in the HBO series The Newsroom and Scott Pilgrim vs. the World, while Treadaway appeared as Victor Frankenstein in the Showtime series Penny Dreadful. Briones recently played a major role in FX's American Crime Story: Versace.

Plot details and the official start date for the planned series have yet to be announced by CBS, but the series is expected to start approximately 18 years after the events of 2002's Star Trek: Nemesis, the final canonical appearance of Picard in the franchise.

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Picard's untitled Star Trek series stars Patrick Stewart, Santiago Cabrera Michelle Hurd, Evan Evagora, Alison Pill, Harry Treadaway and Isa Briones, and is set to debut later this year on CBS All Access.

(via Variety)