Causal
strong strength
Narrative Connection
How these two moments in the story relate
From
Divine Intervention and Hidden Escape
S4E21
·
The Underwater Menace Part 3
To
Ben reveals the hidden passage’s origin
S4E21
·
The Underwater Menace Part 3
Why These Connect
The narrative assertion
"The Doctor and Ramo's escape through the hidden door directly leads the Doctor to question how Ben found it, leading Ben to explain the tunnel in the mines."
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.