When Mr Bean is in the chemistry lab, he pours the blue liquid into the clear liquid, turning it red. In the next shot, Mr Bean is seen putting a beaker of clear liquid on the table, and the beaker of red liquid is already on the table.
At the beginning of the episode, Mr. Bean steals the parking space of the other Mini to park his Mini into that spot; a boom mic and a boom operator in a blue jumper can be seen reflected in the Mini's windows and when the troops take the car away.