"Threshold" is the 31st episode of American science fiction television series Star Trek: Voyager airing on the UPN network, the 15th episode in the second season.

The series follows the adventures of the Federation starship Voyager during its journey home to Earth, having been stranded tens of thousands of light-years away. In this episode, Lieutenant Tom Paris (Robert Duncan McNeill) becomes the first known person in mankind to break the Warp 10 barrier.

Voyager's crew discovers a rare, more stable form of dilithium that they postulate could power a warp drive beyond Warp 10. This would allow Voyager to reach the Alpha Quadrant near instantaneously. Although holodeck simulations prove disastrous, Lieutenant Paris (Robert Duncan McNeill) comes up with an idea after an off-the-cuff discussion with Neelix (Ethan Phillips). The next simulation is successful and a shuttlecraft, dubbed the Cochrane, is prepared for a full test flight. The Doctor (Robert Picardo) identifies a rare medical condition in Lieutenant Paris indicating a 2% chance that he will suffer lethal effects from the test-flight and recommends assigning Ensign Kim (Garrett Wang) as test-pilot. Paris convinces Captain Janeway (Kate Mulgrew) to allow him to fly the shuttle despite the small risk.

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