[ENT] Season 4, Episode 11: Observer EffectRating: 3
There are some pretty great, creepy scenes and ideas in this episode. I particularly like the depiction of memory erasure. When a character we like is in a situation they are helpless to keep from forgetting it’s very effectively disturbing.
The observers refuse to help the crew, even though the crew will ultimately not know about the intervention, in the name of a principle very similar to the Prime Directive. I think this episode serves as a good rebuttal to Dear Doctor, even if Observer Effect only brings the issue up briefly, and mostly as a way to sidestep the idea.
One of the reasons that theme is not as central is because in true Star Trek fashion, humans are so cool and awesome, and they challenge the beliefs of the supposedly more advanced aliens. More on that later…
Read more at Memory Alpha
Notes:

Some aliens take over Reed and Mayweather’s bodies to observe the crew. This is one of the better opening scenes on Enterprise.

The observers want to see how humans react to the situation. Apparently Klingons and Cardassians didn’t do so well. They didn’t create the virus, or do anything to bring people here, but they use a species’ reaction to the virus as a test of whether or not the species should be contacted.
It’s never really clear what kind of reaction the observers consider favorable, since the older one who represents the established ideals of their species doesn’t seem impressed by basically anything. What qualities are they looking for? Even when they concede to Archer’s request later, it’s only the younger observer who is impressed.

We learn that Hoshi was kicked out of the academy because she ran a gambling club, and broke someone’s arm because she’s a black belt in aikido. This sounds like sulu-syndrome character development.

Even though the observers talk about wanting to see how humans react in this situation, T’Pol and Phlox, the two non-humans on Enterprise, do all the hard work.

Hoshi starts to lose it and wants to get out. She can break the security code because “math is just like another language.” No, not really, and just because someone’s good at math doesn’t mean they can breach security doors, right?

In a particularly creepy scene, after Trip and Hoshi are sedated, the observers take over their bodies to have a private place to talk. Phlox sees them!

They realized they’re being watched and inhabit Archer and T’Pol to pay a visit to Phlox. They erase his memory, but not before Phlox gets some good jabs in. It’s a little funny since the observers have a pretty similar position that Phlox championed in Dear Doctor.
Seriously though, Phlox wanted to let an entire species go extinct, these dudes are just letting two people die.

But then Trip becomes inhabited by the observer, who reveals he’s an Organian (those guys from “Errand of Mercy”!)
This episode also leans on something that hadn’t reared its head quite so much this late in the Trek franchise, which is that humans are extra special. This always goes along with a pretty heavy inference that humans are better than all these other stupid aliens. In this case, it’s compassion and illogical persistence that set humans apart. I’m not saying those are bad qualities, but it’s pretty silly that the Organians have studied hundreds and hundreds of species and none of them have ever displayed these qualities.
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