  We prove the prime geodesic theorem for the Picard manifold whose error term
shrinks as the hybrid subconvex exponent $\theta$ for quadratic Dirichlet
$L$-functions over Gaussian integers decreases. Our rate of decay is faster
than that of Balkanova-Frolenkov (2022) and Kaneko (2022), and leads to the
exponent $\frac{202}{139}+\varepsilon$ in the prime geodesic theorem under the
generalised Lindel\"{o}f hypothesis $\theta = 0$, improving upon the existing
conditional results. This provides further solid evidence towards the validity
of the conjectural exponent $1+\varepsilon$.
