If it's a mouse, it'd be more scared of you than you are of it. A mouse is essentially a hamster with a longer tail, don't be afraid.
Put his cage on the floor near the dresser, with the door open (if the door is on the top or somewhere else where the hamster can't walk in on his own, just put a box on its side or something) with a trail of food leading to it, and a special treat inside. Maybe you can lure him into it and catch him.