  Cygnus X-3 is a unique microquasar in the Galaxy hosting a Wolf-Rayet
companion orbiting a compact object that most likely is a low-mass black hole.
The unique source properties are likely due to the interaction of the compact
object with the heavy stellar wind of the companion. In this paper, we
concentrate on a very specific period of time prior to the massive outbursts
observed from the source. During this period, Cygnus X-3 is in a so-called
hypersoft state, where the radio and hard X-ray fluxes are found to be at their
lowest values (or non-detected), the soft X-ray flux is at its highest values,
and sporadic gamma-ray emission is observed. We will utilize multiwavelength
observations in order to study the nature of the hypersoft state. We observed
Cygnus X-3 during the hypersoft state with Swift and NuSTAR in the X-rays and
SMA, AMI-LA, and RATAN-600 in the radio. We also considered X-ray monitoring
data from MAXI and $\gamma$-ray monitoring data from AGILE and Fermi. We found
that the spectra and timing properties of the multiwavelength observations can
be explained by a scenario where the jet production is turned off or highly
diminished in the hypersoft state and the missing jet pressure allows the wind
to refill the region close to the black hole. The results provide proof of
actual jet quenching in soft states of X-ray binaries.
