This particular episode is a nod to the classic noir style, from setting most of the events on a train to the mysterious femme fatale. It also gave the producers an opportunity to put together a “bottle show” to help keep the budget relatively low. Usually a bottle show is structured to force a handful of characters into a set of conflicts that expose psychological motivations and tensions. In this case, the style mitigated the need to delve too deeply into the characters.
Maggie was a mass of contradictions, and that is key to the success of the episode. To ensure that the conventions of the noir style were obeyed as much as possible, Maggie took on a personality that wasn’t well maintained. In some scenes, her performance was quite good. In others, her delivery was too modern.
The most favorable interpretation is that the character is inherently modern herself, so her current personality is a façade. She is attempting to create the right kind of attitude to fit into a fantasy. As a con artist, this is what she does, and so it makes sense that the effectiveness of the illusion would come and go with her confidence in the necessity of her actions. With Johnny, she enjoyed playing the role as well, complicating the motivations.
On the other hand, it’s possible that the writers wanted Maggie to fit into the iconic noir mold from beginning to end, and the actress just couldn’t pull it off. With some of the recent casting woes (at least from my point of view), this wouldn’t necessarily be a surprise. But this has also been a restorative season in many respects, and even if the days of high profile guest casting are over, this was hardly as bad as some previous choices.
Maggie also brought up the ongoing issues with Johnny and Sarah. Maggie recognizes that Sarah is still the woman in Johnny’s life, despite the fact that circumstances continue to make any current chance of romance non-viable. It’s mentioned enough in the episode to make it somewhat obvious that Johnny’s feelings will become important later in the season. In fact, it would be interesting, having established this much, for Sarah to wander in another direction.
Whatever the case, as a stand-alone “bottle episode” of the series goes, this is about average. Some stand-alone episodes of the first couple seasons were better, but this is certainly better than the last few seasons had produced.