"Final Mission" is the 83rd episode of the American science fiction television series Star Trek: The Next Generation, and the ninth episode of the fourth season. After learning that he finally has been accepted into Starfleet Academy, Wesley Crusher welcomes Picard's invitation to accompany him on an away mission that could resolve a mining dispute on an arid world. But following a shuttle crash and a near disastrous search for water that leaves the captain near death, Wesley finds himself charged with the weighty responsibility of keeping both himself and Picard alive until a rescue team can locate them.

The Enterprise has traveled to the Pentarus system where Captain Picard (Patrick Stewart) must mediate a dispute among some miners on the fifth planet. Wesley Crusher (Wil Wheaton) receives word that he has been accepted to Starfleet Academy and, for his final mission, he will accompany Picard on his shuttle trip to Pentarus V. A distress call comes in from Gamilon V, where an unidentified vessel has entered orbit and is giving off lethal doses of radiation. Picard orders Riker to take the Enterprise to resolve that situation while he and Wesley travel in a shuttle sent by the miners, commanded by Captain Dirgo.

En route, Dirgo's shuttle malfunctions and they are forced to crash-land on the surface of a harsh, desert-like moon. Though they are unharmed, the shuttle is beyond repair, and its communication systems and food replicators are disabled. Dirgo admits he has no emergency supplies on board, so they are forced to search for shelter and water. With his tricorder, Wesley identifies some caves and a potential source of water some distance away, and the three set out across the desert. Reaching a cave, they find a fountain-like water source, but it is protected by a crystalline forcefield. Dirgo attempts to use a phaser to destroy the field, but this activates a burst of energy from the fountain which encases the phaser in an impenetrable shell and causes a rock slide; Picard pushes Wesley out of the way but is severely injured in doing so.

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