Octupole Strength in the $^{238,240,242}$Pu isotopes*

A series of so-called ``unsafe'' Coulomb excitation experiments as well as 1-neutron transfer measurements was carried out with Gammasphere at the ATLAS accelerator in order to investigate the collective properties of $^{238,240,242}$Pu. New experimental evidence has emerged that in $^{240}$Pu a transition from an octupole vibration to stable octupole deformation occurs at high spin. A similar situation may be present in $^{238}$Pu, but is clearly absent in the heavier $^ {242}$Pu. The data will be presented and discussed together with available information on neighboring nuclei in the region.