Snowpiercer finally remembers the questions of survival

After a fairly slow two introductory episodes to the final season, "Life Source" finally remembers, at least to a degree, the desperation, anguish, and controversy that comes with making decisions in order to survive, or in Layton's case, reunite with a loved one.

Following his daughter's kidnapping, Layton's only motive and goal is to reunite with Liana, no matter what it takes. Layton's anguish and desperation means that he will go above and beyond the council to achieve his goal, and this mix of desire and controversy is what this episode does best. Layton's motives are completely justified. His daughter was taken and he needs her back. However, in order to do that, Layton needs to take Big Alice's engine with him to catch Snowpiercer, which could put the survivors in New Eden at risk. Does Layton take the engine to reunite with his daughter? Or, does he leave the train be for the remaining survivors?

While Layton desperately fights for Liana, Ruth takes on the opposing argument in favor of the rest of the survivors in New Eden. In Ruth's perspective, she can not put all of their lives at risk, even as much as she wants Liana back. This is part of what the show does best, forcing their main characters to interact, or conflict, with two opposing concepts that make complete sense to the individual characters, and letting them work it out.

Layton and Ruth are two people who have known each other for a while, relied on each other, and respected each other. They know each other well enough to understand the other's perspective, even if they are both temporarily blinded by tunnel vision. Nothing about their divide in "Life Source" is personal.

Daveed Diggs steps up offering Layton's anguish, desperation, and determination in a way that the character shows himself to be entirely devoted to Liana, even at the expense of hurting the feelings of others he loves, and who he knows loves his daughter too. Layton is an emotional time bomb in a way that truly works for "Life Source."

The ultimate decision, removing the board from the choice and leaving it to a democratic vote, proves that Layton's plight is respected by the group, and Ruth reveals the news with specific rules, including that Big Alice must return to New Eden in three weeks to ensure the survival of the rest of everyone else.

Alex's scientific revelation adds more stakes and weight to that time period, as her question of if they exist in a permanent warm spot or temporary warm bubble that could pop any day hangs over Javi's head as Big Alice leaves for what is supposed to remain a three-week expedition.

But, for all the emotional moments that New Eden faces, "Life Source" has not brought the same life to the events on Snowpiercer, and Melanie's absence continues to haunt the show. Melanie is one of the strongest presence's on the show, so Snowpiercer's dedication to reducing her role after season one continues to make less sense as time goes on.

Melanie is one of the strongest foundations of the show, so to have her go from a strong presence in season one, to reducing her role in the two subsequent seasons, and then having her absent again in "Life Source" hurts the show. While Layton and Wilford's rivalry may have been able to hold the show together during Melanie's other absences, that is not the case in season four, and Melanie's absence is very noticeable in "Life Source."

Ben and Till's rivalry with season four's new villain, Admiral Milius, is dull at best. Admiral Milius does not have Wilford's charisma, intelligence, or strategic thinking. Instead, he rules Snowpiercer with a brutal iron fist turning the train's survivors into a labor force and threatening their lives under the guise of protecting humanity.

Although "Life Source" does get the plot moving by having Layton and his friends heading in the direction of Snowpiercer, things will still not come to an exciting head until Snowpiercer has finally brought about the season's most anticipated reunions.