In terms of sheer action, this almost standalone episode was one of the best of the series so far, with Rufus having to cobble together a fix for the damaged machine, as well as tell the future when and how to expect them, and the rest of the team doing what they do best - speaking French (Lucy) and fighting off the bad guys (Wyatt) as enjoyably needed.
There are some fine new classic time-travel touches in this episode, my favorite being the time-capsule that Rufus buries deep in the ground with instructions for the future. It will end up in a Pittsburgh suburb, no longer inhabited by the Native Americans who play a major role in this story, along with the French. Rufus buries the capsule subject to a "protocol" which was designed to be implemented for strandings like this.
The last few minutes of the episode switch from swashbuckling to metaphysics, something that goes beyond the physics speciality in which Rufus excels. Lucy is feeling drawn into writing the diary which Flynn has shown her and told her she will write. The diary symbolizes everything that Lucy doesn't want - not only being connected to Flynn, but having her future prescribed to her.
Wyatt argues that nothing is ordained, and free will prevails. Of course, this is impossible to prove. If we do something, and say it's our free expressing itself, how can we know for sure that we weren't destined to do that anyway, and free is just a comforting illusion we draw upon and wrap ourselves in to make us feel better?
This is the essence of the classic behaviorist theory devised in the first half of the 20th century by John B. Watson and expanded by B. F. Skinner - that everything we do is in response to some kind of conditioning, whether we're aware of it or not. An issue of such complexity could never be resolved in just a few minutes of a time-travel television series, but it's great to see it raised, anyway.
See also Timeless 1.1: Threading the Needle ... Timeless 1.2: Small Change, Big Payoffs ... Timeless 1.3: Judith Campbell ... Timeless 1.4: Skyfall and Weapon of Choice ... Timeless 1.5: and Quantum Leap ... Timeless 1.6: Watergate and Rittenhouse
a time-travel agency in Riverdale ....