A Dangerous Mission

Walker and Alan take on a dangerous mission to destroy the virus on Helix. "Level X" is the ninth episode of the show's first season.
Added:

Helix Season 1 Episode 9 Quotes

It's like a who's who of mass epidemics in here.

Alan

Julia: When I was hallucinating, he [Peter] said it's about you Julia,
it's always been about you.
Alan: Might have been your subconscious talking.
Julia: Or it might be the reason we're all here.