Complex sentence: When he got back to the fire, he looked like one of the real firemen, so nobody noticed him or questioned him as he slipped right past the real men, walked right into the house, and retrieved the incriminating object.
Split into simpler sentences: When he got back to the fire, he looked like one of the guys. Nobody noticed him or questioned him as he walked right past the real firemen, right into the house, and retrieved the incriminating object.