  We demonstrate single-shot imaging and narrow-line cooling of individual
alkaline earth atoms in optical tweezers; specifically, strontium-88 atoms
trapped in $515.2~\text{nm}$ light. We achieve high-fidelity
single-atom-resolved imaging by detecting photons from the broad singlet
transition while cooling on the narrow intercombination line, and extend this
technique to highly uniform two-dimensional arrays of $121$ tweezers. Cooling
during imaging is based on a previously unobserved narrow-line Sisyphus
mechanism, which we predict to be applicable in a wide variety of experimental
situations. Further, we demonstrate optically resolved sideband cooling of a
single atom close to the motional ground state of a tweezer. Precise
determination of losses during imaging indicate that the branching ratio from
$^1$P$_1$ to $^1$D$_2$ is more than a factor of two larger than commonly
quoted, a discrepancy also predicted by our ab initio calculations. We also
measure the differential polarizability of the intercombination line in a
$515.2~\text{nm}$ tweezer and achieve a magic-trapping configuration by tuning
the tweezer polarization from linear to elliptical. We present calculations, in
agreement with our results, which predict a magic crossing for linear
polarization at $520(2)~\text{nm}$ and a crossing independent of polarization
at 500.65(50)nm. Our results pave the way for a wide range of novel
experimental avenues based on individually controlled alkaline earth atoms in
tweezers -- from fundamental experiments in atomic physics to quantum
computing, simulation, and metrology implementations.
