  We consider the asymptotic behavior of the KPZ fixed point $\{\mathsf
H(x,t)\}_{x\in\mathbb R, t>0}$ conditioned on $\mathsf H(0,T)=L$ as $L$ goes to
infinity. The main result is a conditional limit theorem for the fluctuations
of $\mathsf H$ in the region near the line segment connecting the origin
$(0,0)$ and $(0,T)$ for both step and flat initial conditions. The limit random
field can be represented as a functional of two independent Brownian bridges,
and in addition the limit random field depends also on the initial law of the
KPZ fixed point. In particular for temporal fluctuations, the limit process
indexed by line segment between $(0,0)$ and $(0,T)$, when the KPZ is with step
initial condition, has the law of the minimum of two independent Brownian
bridges; and when the KPZ is with flat initial condition the limit process has
the law of the minimum of two independent Brownian bridges, each in addition
perturbed by a common Gaussian random variable. For spatial-temporal
fluctuations, the conditional limit theorem sheds light on the asymptotic
behaviors of the point-to-point geodesic of the directed landscape conditioned
on its length and as the length tends to infinity.
