Phlox is kidnapped on earth and events involving Malcolm Reed start to get a bit cloak and dagger.
This is an enjoyable episode with a lot going on and some strong performances, however it needs to be watched with knowledge of several other Enterprise episodes and Star Trek shows, along with a desire for an explanation why the Klingons look different to the one shown in original series.
Thankfully the plot is pretty intriguing, with connections to other events in several other episodes of Enterprise, the original series and Deep Space Nine. The stories involving the Klingons and Reed are pretty compelling and make me want to find out what happens next. There is a sub-plot involving the Trip/T'Pol romance which is better than what has come before, but it still hasn't got an emotional investment from me in whether they end up together or not.
All performances are spot on and for me, as always in Enterprise, it is the guest stars that steal the show. James Avery, otherwise known as Uncle Phil from "Fresh Prince Of Bel-Air" seems like he was born to play a Klingon at some point in his career. John Schuck is also excellent as a Klingon doctor in several scenes with Avery and John Billingsley, who is great as always as Phlox.
A lot of thought seems to have gone into the explanation for why the Klingons portrayed in the original series look different to the ones with the cranial ridges developed as the make-up effects modernised. This is a good enough explanation for me, but I hope this is not all the two-parter boils down to in the end. Overall, though it's a good start.
For me the episode is 7.5/10, but as always I round upwards.