"Final Mission" is an episode of the science fiction television series Star Trek: The Next Generation, and the last one featuring Wesley Crusher as a weekly character. The episode has an average rating of 3.6/5 on the official Star Trek website (as of June 9th, 2007).
Word has come that Wesley Crusher has been admitted into Starfleet Academy and will need to head to Earth to begin studies. Before Wes leaves, however, Captain Picard asks the young ensign if he will join him on a diplomatic mission to Pentarus Five.
As they are about to leave aboard a mining shuttle piloted by Captain Dirgo a distress call comes in from the leadership of Gamilon Five. An unidentified vessel has entered their orbit and its presence has increased radiation across the planet to dangerous levels. The Enterprise speeds off to assist, and the shuttle heads to Pentarus Five.
On the way disaster strikes as one of the shuttle's thrusters is blown off. Dirgo acts quickly and the trio crash land on an inhospitable moon. The shuttle is severely damaged, and will no longer fly, and the communications and food replicators are also smashed. Without any supplies at all, the three look for shelter and eventually stumble upon a cave.
The Enterprise arrives at Gamilon and discovers the ship in question is an abandoned garbage scow full of radioactive waste. Using remote modules the Enterprise crew work on towing the scow away from the planet and through an asteroid field to be dumped in a nearby sun.
Learning that the shuttle has gone missing, the Enterprise crew work more quickly, but have trouble with the remote modules. Riker orders shields extended around the scow to protect the planet from the radiation and they begin slowly towing the ship with a tractor beam through the asteroid belt.
Wes and the others locate a water fountain, but are not able to go near it as it is protected by a force field. Dirgo tries to phaser through the field, but a mysterious energy sentry appears, tosses away Dirgo's phaser, and causes a rockslide. Picard pushes Wes out of the way, but is caught in a hail of rocks.
Captain Picard is badly injured, and Dirgo believes he is done for, but Wes refuses to give up hope. Wes starts studying the energy readings, and concludes the sentry is sensitive to phaser energy. Dirgo disagrees, and convinces Wes that hitting the sentry with two phasers might work. However, the plan fails, and in the process Dirgo is killed.
Meanwhile, the Enterprise finally manages to dispose of the scow and joins the search for the shuttle. In short order, the Enterprise crew locate the shuttle's destroyed thruster and are hot on the trail.
Wes manages to figure out a way to stop the sentry and gets to the water, which he then gives to Picard. The Enterprise arrives and rescues the two. As Picard is carried out of the cave, he tells Wes that he will be missed.