  The black hole interior is a mysterious region of spacetime where
non-perturbative effects are sometimes important. These non-perturbative
effects are believed to be highly theory-dependent. We sharpen these statements
by considering a setup where the state of the black hole is in a superposition
of states corresponding to boundary theories with different couplings,
entangled with a reference which keeps track of those couplings. The
entanglement wedge of the reference can then be interpreted as the bulk region
most sensitive to the values of the couplings. In simple bulk models, e.g., JT
gravity + a matter BCFT, the QES formula implies that the reference contains
the black hole interior at late times. We also analyze the Renyi-2 entropy of
the reference, which can be viewed as a diagnostic of chaos via the Loschmidt
echo. We find explicitly the replica wormhole that diagnoses the island and
restores unitarity. Numerical and analytical evidence of these statements in
the SYK model is presented. Similar considerations are expected to apply in
higher dimensional AdS/CFT, for marginal and even irrelevant couplings.
