Causal
strong strength
Narrative Connection
How these two moments in the story relate
From
Zaroff’s collapse and reactor threat
S4E21
·
The Underwater Menace Part 3
To
Doctor splits team after Zaroff’s collapse
S4E21
·
The Underwater Menace Part 3
Why These Connect
The narrative assertion
"Zaroff reveals the nuclear reactor is activated, prompting the Doctor to determine they must get inside of the laboratory to investigate it."
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.