Tā bèizhe lǎobǎn tōutōu zuò le hěnduō shì, zuìhòu háishì bèi fāxiàn le.
He did many things behind the boss's back and was found out in the end.
Tips
usage
Note the two pronunciations: bēi zhe (carrying physically on one's back) vs bèi zhe (behind someone's back, secretly). 背着我 can mean either 'carrying me on their back' (bēi zhe wǒ) or 'behind my back' (bèi zhe wǒ) - tone matters!