  In February 2017, the blazar OJ~287 underwent a period of intense
multiwavelength activity. It reached a new historic peak in the soft X-ray
(0.3-10 keV) band, as measured by Swift-XRT. This event coincides with a
very-high-energy (VHE) $\gamma$-ray outburst that led VERITAS to detect
emission above 100 GeV, with a detection significance of $10\sigma$ (from 2016
December 9 to 2017 March 31). The time-averaged VHE $\gamma$-ray spectrum was
consistent with a soft power law ($\Gamma = -3.81 \pm 0.26$) and an integral
flux corresponding to $\sim2.4\%$ that of the Crab Nebula above the same
energy. Contemporaneous data from multiple instruments across the
electromagnetic spectrum reveal complex flaring behavior, primarily in the soft
X-ray and VHE bands. To investigate the possible origin of such an event, our
study focuses on three distinct activity states: before, during, and after the
February 2017 peak. The spectral energy distributions during these periods
suggest the presence of at least two non-thermal emission zones, with the more
compact one responsible for the observed flare. Broadband modeling results and
observations of a new radio knot in the jet of OJ~287 in 2017 are consistent
with a flare originating from a strong recollimation shock outside the radio
core.
