The knock at 4 am needed to be answered. Mark groggily made his way to the door, rubbing his eyes and wondering who could possibly be stopping by at this ungodly hour. As he opened the door, he was greeted by a man in a suit, looking official and serious.

“Mr. Johnson, I’m sorry to disturb you so early, but there’s been an incident at the lab. We need your expertise to contain and assess the situation,” the man said.

Mark felt his heart race as he quickly got dressed and followed the stranger to a waiting car. As they drove through the empty streets, the man explained that there had been a breach in the containment system, and a dangerous virus had been released. Mark was the only one with the knowledge and experience to handle the situation.

As they arrived at the lab, Mark donned his hazmat suit and went inside. The scene was chaotic, with scientists scrambling to contain the virus and evacuate the building. Mark quickly assessed the situation and set a plan in motion.

Hours passed as Mark worked tirelessly to contain the virus and develop a cure. The entire city was on lockdown, as news of the outbreak spread. Mark worked through the night, fueled by adrenaline and the knowledge that countless lives were at stake.

Finally, after what felt like an eternity, the virus was contained, and a cure was found. Mark emerged from the lab, exhausted but relieved. He had saved countless lives, and his expertise had been invaluable in stopping the outbreak.

As he headed home at dawn’s early light, Mark felt a sense of pride and satisfaction. He had answered the knock at 4 am and had made a difference in the world.