  The study of RR Lyrae stars has recently been invigorated thanks to the long,
uninterrupted, ultra-precise time series data provided by the Kepler and CoRoT
space telescopes. We give a brief overview of the new observational findings
concentrating on the connection between period doubling and the Blazhko
modulation, and the omnipresence of additional periodicities in all RR Lyrae
subtypes, except for non-modulated RRab stars. Recent theoretical results
demonstrate that if more than two modes are present in a nonlinear dynamical
system such as a high-amplitude RR Lyrae star, the outcome is often an
extremely intricate dynamical state. Thus, based on these discoveries, an
underlying picture of complex dynamical interactions between modes is emerging
which sheds new light on the century-old Blazhko-phenomenon, as well. New
directions of theoretical efforts, like multi-dimensional hydrodynamical
simulations, future space photometric missions and detailed spectroscopic
investigations will pave the way towards a more complete understanding of the
atmospheric and pulsation dynamics of these enigmatic touchstone objects.
