Since Tina joins the journey on the second day in this episode, Episode 5 still features a lot of original content, though some modifications bring the plot slightly closer to the original work.
1.The opening dialogue among WLF members about the spores on the B2 floor of the hospital is original.
In the original work, information about the hospital's B2 floor is revealed in Abby's storyline: this hospital once admitted Seattle's "patient zero," triggering a large-scale infection that eventually led to the city's downfall.
As per the setting, this should be the area with the highest fungal concentration in Seattle. Thus, the series reintroduces the spore element here, though it is presumably confined to the hospital's interior.
2.In the original work, Tina did not join the search on the second day due to severe pregnancy symptoms on the first night, leaving Ellie to search for Nora alone.
However, the series retains the scene where Tina helps Ellie locate Nora via radio, with some dialogue adjustments (primarily the triangulation part; in the game, Tina tracks Tommy's movements for positioning).

3.The series recreates the scene where Ellie plays Future Days—a song Joel taught her on the guitar, holding great significance for him. Unlike the game, where Ellie drifts into memories of Joel after singing the first line, the series delays this flashback to Episode 6.

Mid-episode, Ellie and Tina encounter executed Scar members by the roadside. Ellie, having second thoughts, urges Tina not to risk her safety, but Tina encourages Ellie to continue her revenge by recounting how she killed the perpetrators who massacred her family.

This marks another major revision to character 设定. First, Tina's backstory is rewritten: in the original work, she only mentions killing a poacher who tried to harm her mother, with her family surviving the attack.
In the game, Tina does not specify who killed her sister and mother—only that they died en route to Jackson, with few details provided.
Second, Tina's attitude toward revenge in the series differs drastically from her game counterpart:
In the game, Tina accompanies Ellie to Seattle out of love and concern, not out of a desire for revenge. She even argues that revenge should not disrupt their current life and advises Ellie against dragging unrelated people into the vendetta to avoid escalation.
Though she mentions "killing the culprit harshly" in the game, this is primarily to comfort Ellie; she never actively seeks out her family's murderers.
This change may explain Tina's fervor for revenge in the series, especially with added interactions between her and Joel in Episode 1.
The divergence in their views on revenge in the game leads to a pivotal plot point, and it remains unclear how the series will handle this (likely not until Season 4...).
4.Jesse makes an appearance! His portrayal in the series, however, differs entirely from the game.
In the game, Jesse appears mid-second day. Ellie discovers a WLF patrol attacked by unknown assailants, assuming it to be Tommy, only to find Jesse—who followed out of concern for their safety—and injured. Ellie rescues him, and they escape to rest at the cinema.
Additionally, Tommy's storyline—long a concern for many— is confirmed to exist, ensuring his presence in future episodes.

5.Like the previous episode, Ellie's second day is heavily condensed due to runtime constraints, transforming her from a panicked girl to a vengeful force before Nora.
In the game, Ellie's second day is brutal, bloody, and exhausting. She kills numerous WLF members (nearly everyone in the hospital) and fends off a Scar attack (in the series, Tina is shot with an arrow), leaving her in a deranged state, consumed by revenge, when confronting Nora.
(The famous PSV sequence wasn't even filmed!!)

6.The episode's final scene largely recreates Ellie's killing of Nora, with minor dialogue tweaks.
In the game, Ellie has no idea why Abby's group killed Joel during the first two days. Tina speculates it might be related to Joel's smuggling past, and Ellie is surprised to learn Nora is a Firefly.

In the series, Nora reveals the truth about the Firefly hospital and Joel's actions that day—unlike the game, where she only mentions Joel "having killed many people" without specifics.