  Transitional millisecond pulsars are millisecond pulsars that switch between
a rotation-powered millisecond pulsar state and an accretion-powered X-ray
binary state, and are thought to be an evolutionary stage between neutron star
low-mass X-ray binaries and millisecond pulsars. So far, only three confirmed
systems have been identified in addition to a handful of candidates. We present
the results of a multi-wavelength study of the low-mass X-ray binary NGC 6652B
in the globular cluster NGC 6652, including simultaneous radio and X-ray
observations taken by the Karl G. Jansky Very Large Array and the Chandra X-ray
Observatory, and optical spectroscopy and photometry. This source is the second
brightest X-ray source in NGC 6652 ($L_{\textrm{X}}\sim1.8\times10^{34}$ erg
s$^{-1}$) and is known to be variable. We observe several X-ray flares over the
duration of our X-ray observations, in addition to persistent radio emission
and occasional radio flares. Simultaneous radio and X-ray data show no clear
evidence of anti-correlated variability. Optical spectra of NGC 6652B indicate
variable, broad H $\alpha$ emission which transitions from double-peaked
emission to absorption over a time-scale of hours. We consider a variety of
possible explanations for the source behaviour, and conclude that based on the
radio and X-ray luminosities, short time-scale variability and X-ray flaring,
and optical spectra, NGC 6652B is best explained as a transitional millisecond
pulsar candidate that displays prolonged X-ray flaring behaviour. However, this
could only be confirmed with observations of a change to the rotation-powered
millisecond pulsar state.
