Theory:

The play "If I Were You," written by Douglas James, has 'Gerrard' as the protagonist. The play would start with Gerrard's talk with someone over the phone. He packed his bag as soon as he got off the phone since he had plans to travel somewhere. However, a man had entered Gerrard's cottage without his knowledge, and he remarkably resembled Gerrard. He was holding a handgun. When Gerrard noticed him, the intruder insisted that Gerrard answer all of his questions, threatening to shoot him if he didn't.
 
Despite the fact that Gerrard had no clue why the intruder had broken into his residence, he was able to obtain information from the intruder after some time. The intruder inquired about Gerrard's car, Christian name, and other personal details, telling Gerrard that he already knew Gerrard's personal information and was verifying it with him.
 
As far as the intruder knew, Gerrard lived alone in his cottage, possessed a car, avoided meeting any tradespeople, and lived a life of mystery. During their conversation, each of them had shared a lot about themselves. Gerrard was informed that the intruder was planning to murder him since he had chosen to steal and use Gerrard's identity after he was dead. As the intruder was a thief and a killer, he wanted to take advantage of his resemblance to Gerrard.
 
Gerrard had skillfully presented a tale about himself as a crook and a killer when he learned the intruder's purpose for killing him. He persuaded the intruder that murdering him would be pointless because he would still be hung as Gerrard. The intruder would then be persuaded to assist him in eluding the cops in Gerrard's car. When the intruder trusted Gerrard's statements, he would lead him to a door that looked like a garage door but was actually a cupboard door. When the intruder went to inspect the way, Gerrard trapped him within the cupboard. Gerrard's intelligence and presence of mind rescued his life in the end.