Revealing mistake: When Matrix sends Sully to his death by dropping him off the edge of the cliff, in the shot of Sully falling it is an obvious dummy. (00:39:20)
Revealing mistake: During the airport scene involving the thug, Cindy and Matrix, the same extras are seen walking around the place over and over again.
Revealing mistake: When Cindy and Matrix enter the parking lot, Matrix / Arnold's stand-in is very noticeable, haircut and colour completely different. (00:31:05)
Revealing mistake: Just before we see the boat explode at the start, a wire/cable holding the boat in place can be seen at the bottom of the screen. (00:04:10)
Revealing mistake: When Matrix reaches Arius' mansion (in actuality the Harold Lloyd Estate), he is rushed at by several soldiers of Arius' private army and starts shooting at them with his RPK. In one shot from Matrix's rear we can see him shooting four soldiers at the same time. However, the two soldiers on the far left drop dead even though Matrix is aiming his weapon to the right. (01:11:40)
Answer: They didn't know where Matrix lived. They were killing Matrix's old unit because they knew if they did General Kirby would make physical contact with Matrix to warn him. They simply followed Kirby to Matrix's home.
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