For a connected open subset Ω of the plane and n a positive integer,
let Bn(Ω) be the space introduced by Cowen and Douglas. In this article we study the
spectrum of restrictions of T in order to obtain more information about the invariant
subspaces of T. When n=1 and T ϵ B1(Ω) such that σ(T)=Ω¯ is a spectral set for T we
use the functional calculus we have developed for such operators to give some infinite
dimensional cyclic invariant subspaces for T.