Main Points And Long Answer
If I were you
Question 1.
Why was Gerrard packing a bag at the beginning of the play? How did it help him to outwit and trap the Intruder?
Answer:
Gerrard was packing a bag in the beginning of the play as he had to deliver some props to some theatrical company for rehearsal. When the Intruder broke into his cottage and threatened to kill him and steal his identity, Gerrard did not lose his cool. He spontaneously concocted a story that he himself was a criminal and was trying to dodge the police. This story was supported by the aura of mystery that surrounded him, his reclusive lifestyle, the bag he had been packing, the disguise outfit, false moustaches etc.
All this misled the Intruder into believing that Gerrard was speaking the truth. He did not doubt Gerrard any longer and unsuspectingly got ready to escape along with him. When Gerrard indicates the door that leads straight to the garage, the Intruder walks into a trap. Hence, the bag played an important role in convincing the Intruder that Gerrard, too, was a criminal like him and was preparing to flee when he broke into his cottage.