A mysterious life form known as the 'Nagilum' threatens the life of the crew in his attempt to understand humanity.

When Data's rights as a sentient individual are placed under trial, Starfleet forces Riker into a position where he must prove that Data is only an Android.

Picard encounters his double from six hours in the future, whose Enterprise had been destroyed.

Q hurls the Enterprise into the Delta Quadrant and introduces the Federation to a powerful new enemy that may destroy the Alpha Quadrant: The Borg.

A rift in the space/time continuum brings the U.S.S. Enterprise - C forward into the 24th Century, and alters the timeline. In this future, the Federation is at war with the Klingons, Tasha Yar is on the bridge, Worf did not join the Federation, and only Guinan's unique perception of reality may restore the timeline.

Worf is reunited with his long-lost brother when their father is charged with treason for helping the Romulans. Together they make an appeal to the Klingon High Council to challenge the charges, and have them revoked.

An Starfleet expert on the Borg, Lt. Cmdr. Shelby, is assigned to the Enterprise to investigate the disappearance of a Federation colony. Picard is abducted by the Borg and assimilated into the Collective, which forces Riker to attempt a rescue mission.

Riker must pull out all the stops in order to save Earth from a Borg invasion being lead by none other than Locutus - otherwise known as Captain Jean-Luc Picard.

Riker is abducted by a xenophobic race of aliens during a first contact mission. They believe the Enterprise is a scout for an invasion.

Worf must choose between his people and the Federation when a civil war threatens to destroy the Klingon Empire.

Picard suspects a Romulan influence in the recent Klingon civil war, and must force the Federation to intervene before the Empire collapses.

While exploring the Typhon Expanse, the Enterprise is caught in a time warp in which they are repeatedly destroyed while colliding with another starship.

Wesley is involved in a cover-up at Starfleet Academy when a cadet is killed and five shuttles are destroyed during a forbidden maneuver performed by Starfleet Academy's best cadets.

Picard is struck by an energy beam from an alien probe, which renders him unconscious and places him in the life of a citizen on the planet Kataan, with his memory of the Enterprise intact. Although he searches for a way to return, he finally decides to live his life with his Kataan wife, have children & grandchildren, learning to play a flute and completely immersing in the Kataan culture.

Picard resigns as Captain of the Enterprise to lead a top-secret espionage mission into Cardassia with Worf and Dr. Crusher.

Picard is captured and tortured by the Cardassians, while Riker tries to prevent a Federation attack on Cardassia.

A mortally wounded Picard is forced into re-living a time of his life when he was back in Starfleet Academy, with the intervention of Q.

Riker questions his sanity when his reality seems to shift between an alien psychiatric hospital and a play he is performing with other members of the crew.

Four young ensigns compete for a promotion that only one of them will receive. However, they are soon placed on a top secret mission that places some of their lives in danger.

Shortly after Picard is diagnosed with a long-term, potentially debilitating brain disorder, he starts experiencing bizarre shifts into three main time periods: 25 years into the future, a few days before the Enterprise-D is sent on its mission to Farpoint station, and the present. Picard realizes that Q is behind these shifts through time. Q finally reveals himself that humanity is still on trial, and that Picard must stop an event in the future that will halt the formation of life on Earth four billion years ago.

After his encounter with Q, Picard assembles the senior staff, and wonders if Q is actually giving him a chance to save humanity by showing him that the spatial anomaly also exists in the past. As they talk, the ship reaches the Neutral Zone, then Picard returns to the future, where Beverly's ship is also on the edge of the Neutral Zone. He convinces a reluctant Worf to accompany the group into Klingon territory, and then travels to the past, where he orders the crew into the Devron system. Finally, he returns to the present, where he is able to get Tomalak, the Romulan Commander on the other side of the border, to agree to entering the Neutral Zone together. Now heading for the anomaly in all three time periods, Picard learns that it exists in the present, and is larger in the past, but does not exist in the future.