Upon arrival client showed us the ceiling of the main floor office which had multiple wet spots on the ceiling. Spots are directly below the master shower and tub. Shower shows discoloration on the grout lines and is also backing up causing the pan to fill with water. Opened Sheetrock below to try and locate the leak source. No visible signs of water below or around the drain assembly. Water damage is likely caused by a failed shower pan or pan liner. Advised client about water mitigation and the drain backing up. Client opted to leave the plastic down until the mitigation is completed.