Investigating the disappearance of the USS Drake, the Enterprise away team beams down to the remains of a destroyed civilization on the planet Minos to search for answers. Instead, they come under attack by an advanced weapons system that first employs deceptive intelligence-gathering tactics before turning to simple but unremitting brute force. When Riker is incapacitated by an energy field, Picard beams down, leaving Geordi in command of the Enterprise.
Here's an episode of TNG that drops all pretense of significance and simply exists as action and watching the characters work the crises. The results are pretty good; it's one of the season's better outings, and certainly one of the best-paced. The weapons that attack the away team are like levels in a video game, where after you destroy one, another comes 12 minutes later, except this time stronger and smarter. The episode benefits from its three-pronged plot approach. Riker, Data, and Yar must play infantry in fending off the weapons on the surface; Picard and Crusher fall into a deep hole and the captain must treat the injured doctor as a patient; and La Forge gets his first big test in command when the Enterprise is attacked by an invisible weapon orbiting the planet.
All the plot threads work, but the most interesting is Geordi's on board the Enterprise. He must assume big responsibilities and make tough calls in a dangerous situation. All the while he must put up with Lt. Logan (Vyto Rugins), the Enterprise's chief engineer (or should I say this week's chief engineer, since there's a different one nearly every week on season one), who outranks Geordi and tries to bully him into ceding command to him. If the episode has an evident flaw, it's that Logan is too much of an obvious progress impediment in needlessly challenging Geordi. Someone needs to tell him that instead of repeatedly coming to the bridge he needs to be doing his damn job. And I tend to grow impatient with any scene where Troi counsels the commanding officer with compliments and suggestions, coming off like a kindergarten teacher. Just imagine that in the current-day military.
The episode has some nifty set-pieces, including a prudent saucer separation and the ensuing tactical action. The solution to the problems on the surface are handily wrapped up with what on TOS would be Kirk Outsmarts the Computer™ — except in this case it's Picard and the computer is designed to be outsmarted in this way.