“After dropping off some colonists in a nearby system, the crew visits a world of beautiful, healthy and tanned human-looking people.”
I used to think of this only as a Wesley episode but it is much more than that. Wesley most certainly plays a part in the episode but its themes are steeped in Prime Directive lore.
They have found a society that is seemingly perfect, everyone is healthy and there is no crime. However Tasha finds out there is no crime because all crime is punished by death. Something they didn’t know till after they had split up. Wesley finds himself in trouble when he falls into a garden, disturbing new plants, which is a crime.
In the meantime the Enterprise encounters a ship in orbit, one that the inhabitants of the planet thinks is God. The ship uses Data as a means of an information transfer. The God Ship learns all Data knowns, including about the Prime Directive. They command the Enterprise to not interfere with their “Children” aka, the inhabitants of the planet. Which is unfortunate since they are now forced to deal with the death sentence levied against Wesley.
This is where the crux of the episode comes into play. Picard is forced to either follow the Prime Directive and let Wesley die, or to break the Prime Directive, saving Wesley but possibly putting the ship in harms way due to the threat of the ship in orbit.
Wesley understands the situation and volunteers to let himself be executed, but Picard will not hear it. There is a back and forth between Captain Picard and the inhabitants of the planet, but in the end Picard is not willing to sacrifice Wesley for the sake of the Prime Directive.
Picard makes an impassioned speech to the Ship in orbit, hoping that they will understand that laws should not be an absolute and the ship appears to agrees and lets the Enterprise go.