  We present the analytic formula for the Energy-Energy Correlation (EEC) in
electron-positron annihilation computed in perturbative QCD to
next-to-next-to-next-to-leading order (N$^3$LO) in the back-to-back limit. In
particular, we consider the EEC arising from the annihilation of an
electron-positron pair into a virtual photon as well as a Higgs boson and their
subsequent inclusive decay into hadrons. Our computation is based on a
factorization theorem of the EEC formulated within Soft-Collinear Effective
Theory (SCET) for the back-to-back limit. We obtain the last missing ingredient
for our computation - the jet function - from a recent calculation of the
transverse-momentum dependent fragmentation function (TMDFF) at N$^3$LO. We
combine the newly obtained N$^3$LO jet function with the well known hard and
soft function to predict the EEC in the back-to-back limit. The leading
transcendental contribution of our analytic formula agrees with previously
obtained results in $\mathcal{N} = 4$ supersymmetric Yang-Mills theory. We
obtain the $N=2$ Mellin moment of the bulk region of the EEC using momentum sum
rules. Finally, we obtain the first resummation of the EEC in the back-to-back
limit at N$^3$LL$^\prime$ accuracy, resulting in a factor of $\sim 4$ reduction
of uncertainties in the peak region compared to N$^3$LL predictions.
