Narrative Connection
How these two moments in the story relate
Why These Connect
The narrative assertion
"Tegana's successful manipulation of Polo into seizing the TARDIS in Episode 17 leads directly to Marco hiding the TARDIS keys in Episode 18 to prevent further escape attempts."
inferred by llm_cross_episode_arc
Why This Matters Across Episodes
The longer arc this connection carries
Tegana's influence causing Polo to seize the TARDIS and key creates a direct consequence in Episode 18 where Polo takes extreme measures to secure the keys, raising the stakes for the Doctor's group.
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.