Heartwarming In Hindsight: Nima's hallucinating while in the car next to Jess comes off as bizarre the first time around, and Jess has to use Spanish to ask Nima to rest. This takes on an extra poignancy the second time around, when it's revealed that Nima has a daughter, and mistook Jess as her own during the hallucination.
Gerry giving his daughter confidence when she starts having doubts about her plan to escape the Rotunda.
In Episode 3, after seeing that Oscar, Billy and Nima survived the helicopter crash, Jess runs up to them and hugs them one by one.
The "cornered" death scene in Episode 4, where Gerry and Jess accept that it's the end and silently hug as they are surrounded by Troodon, is as touching as it is sad.
If Nima dies at the end, Gerry and Jess mourn while the island shrinks behind them, but then Gerry resolves to keep his promise to his former companion.