The Shadownip (ENT S2 : E2)

We head back into the time to the days of Sputnik, I Love Lucy, and...secret first contact between T'Pol's great, great grandma and the world's nicest coal mining town in "Carbon Creek". We get an out-of-place, late season filler episode that isn't terrible, and also features the most blatant sexual exploitation to date! Truly this one has everything!