  We investigate joint low-latency gravitational wave (GW) detection and prompt
electromagnetic (EM) follow-up observations of coalescing binary neutron stars
(BNSs). Assuming that BNS mergers are associated with short duration gamma ray
bursts (SGRBs), we evaluate if rapid EM follow-ups can capture the prompt
emission, early engine activity or reveal any potential by-products such as
magnetars or fast radio bursts. To examine the expected performance of extreme
low-latency search pipelines, we simulate a population of coalescing BNSs and
use these to estimate the detectability and localisation efficiency at
different times before merger. Using observational SGRB flux data corrected to
the range of the advanced GW interferometric detectors, we determine what EM
observations could be achieved from low-frequency radio up to high energy
$\gamma$-ray. We show that while challenging, breakthrough multi-messenger
science is possible through low latency pipelines.
