Relativity

Moments after Voyager is destroyed by a temporal explosion, Seven of Nine is pulled into the 29th century by Captain Braxton of the timeship Relativity. Her Borg implants make her the ideal agent to find the device, which was planted somewhere in Voyager's past. Disguised as a Starfleet ensign, she is sent to the Utopia Planitia shipyards in 2371, just as Janeway is first touring her new ship. Repeated time jumps take a toll on her body, and when one version of Seven can go no further, an earlier Seven is recruited. Sent to the middle of a Kazon attack, she enlists Janeway's help, and they discover the culprit is a future Braxton, driven to revenge by the years he lost after his last encounter with Voyager. Janeway herself is sent back to catch him in the act. Braxton is arrested, and Lt Ducane returns Janeway and Seven to their own time, the timeline restored.