  We consider the one-dimensional Schr\"{o}dinger operator in the semiclassical
regime assuming that its double-well potential is the sum of a finite
"physically given" well and a square shape probing well whose width or depth
can be varied (tuned). We study the dynamics of initial state localized in the
physical well. It is shown that if the probing well is not too close to the
physical one and if its parameters are specially tuned, then the {\it tunnel
catch effect} appears, i.e. the initial state starts tunneling oscillations
between the physical and probing wells. The asymptotic formula for the
probability of finding the state in the probing well is obtained. We show that
the observation of the tunnel catch effect can be used to determine the energy
level of the initial state, and we obtain the corresponding asymptotic formula
for the initial state energy. We also calculate the leading term of the
tunneling splitting of energy levels in this double well potential.
