furtive

marked by quiet and caution and secrecy; taking pains to avoid being observed

Stolen; obtained or characterized by stealth; sly; secret; stealthy; as, a furtive look.

Latin 'furtum' - theft

“De Craye saw him cast a furtive eye at his heels to make sure he was not followed, and thought, "Jove! he may be fond of her.”

— George Meredith, Complete Project Gutenberg Works of George Meredith

Hamid, peering furtively around Abuja's bustling market, clutched a small, suspiciously sourced parrot. Every "squawk" made him jump higher than the last raindrop from a monsoon. If caught, he'd squawk louder than the bird.

Anya slipped through the narrow alleys of Marrakech's medina, her eyes darting from shadow to shadow. Under the flickering light of a lone lantern, she pressed herself against a wall, her fingers brushing past the rough texture of ancient plaster as she moved with furtive steps, avoiding the creaky wooden doorsteps.

“Other adjectives discussed by Holmes and Kerouac were "found" and "furtive".”