A laser peening apparatus is available for laser peening a hidden surface of a workpiece, the hidden surface not being line-of-sight accessible to laser energy for treatment thereof. The apparatus includes a pulsed laser system and a laser directing unit. The pulsed laser system is configured for generating the laser energy used for laser peening. The laser directing unit operatively receives and channels the laser energy generated by the pulsed laser system. The laser directing unit includes a laser transmission end and is capable of variably and selectively positioning that laser transmission end. The laser directing unit is thereby configured for variably and selectively directing laser energy upon the hidden surface via the laser transmission end.