Causal
strong strength
Narrative Connection
How these two moments in the story relate
From
Barbara’s horror at insecticide’s scale
S2E2
·
Dangerous Journey
To
Ian Spots the Doctor and Susan
S2E2
·
Dangerous Journey
Why These Connect
The narrative assertion
"Realization of potential communications with Susan influences Ian to locate the source of her voice."
About Causal Connections
A directly causes B. The first event sets forces in motion that produce the second. These are the load-bearing connections of plot--remove one and the story structure collapses.