  We present results from an ongoing study of the phase diagram of (2+1)-flavor
QCD using the HISQ action with smaller than physical light quark masses in the
Roberge-Weiss (RW) plane on lattices with temporal extent $N_\tau=4$. We find
that the endpoint of the $1^{st}$ order RW transition line remains $2^{nd}$
order at least down to light quark masses corresponding to Goldstone pion
masses of $55$ MeV. Furthermore, we show that the chiral condensate is
sensitive to the RW transition and may serve as a energy-like operator
characterizing universal behavior close to the RW endpoint.
