  The structure and decay dynamics for $0^+$ and $2^+$ continuum excitations of
$^{26}$O are investigated in a three-body $^{24}$O+$n$+$n$ model. The validity
of a simple approximation for the cross section profile for long-lived $2n$
emission is demonstrated. A sequence of three $0^+$ monopole ("breathing mode"
type) excited states is predicted. These states could probably be interpreted
as analogues of Efimov states pushed in the continuum due to insufficient
binding. The calculated energies of the $2^+$ states are related to the
excitation spectrum of $^{25}$O. We discuss the correlation between the
predicted $^{26}$O spectrum and experimental observations.
