As Ethan Hunt and the others began their mission, Jiang Yan Hai naturally left. If he stayed, they probably would not have felt at ease.
What they did not know was that the moment Kurt Hendricks came up, Er Dan had silently locked onto his location, including the signals emitted by every communication device on him.
That included the isotope tracker smeared onto the documents in the data case Benji had given Ethan Hunt. Er Dan could capture every signal. When it came to Electronic Warfare, Er Dan was the professional.
Jiang Yan Hai was waiting in the stairwell on the 119th floor. From where he stood, he could see the elevator lobby. The reason he was waiting there was that he wanted to save the scientist. As for why he wanted to save him...
You could never have too many scientists or tech nerds.
He was roughly eighteen meters from the elevator lobby. He had chosen that distance because he wanted to save the man without stopping Kurt Hendricks from leaving.
Although the hotel's systems had previously been under Benji's control, Benji now had to cooperate with Ethan and the others' act. So nearly all the hotel's systems were currently under Er Dan's control on Jiang Yan Hai's side.
At the same time, Jiang Yan Hai continuously heard Benji and the others' conversations with the enemy through his earpiece. When Jane's words, "It's been a pleasure doing business with you," came through, the two people marked by Er Dan in his field of vision quickly emerged from a room.
As the two hurried toward the elevator, Jane's warning sounded in their ears.
"Vistron has left with the real codes."
"Er Dan, adjust the elevator's speed," Jiang Yan Hai instructed in his mind.
"Yes, Commander. The elevator speed has been