All you might feel is someone brush by you and a slight pin prick. But very quickly you would be suffering muscle paralysis followed by suffocation. You would be dead within a very short period of time.
This is the deadly effect of just one of the weapons found on a failed North Korean assassin last year on the busy streets of Seoul, now shown exclusively to CNN. Disguised to look like a Parker ballpoint pen, it contains a poison needle and is practically impossible to identify as a weapon.
The second pen shoots a poison-filled bullet which penetrates the skin and releases the toxin and the third weapon is a flashlight, loaded with up to three bullets. They all look completely innocuous but all three will kill.
An individual willing to be identified only as an "investigation official" showed CNN the weapons, pointing out the flashlight as the most significant find. "This flashlight is new," the man familiar with North Korean assassination devices said.
"I've never seen this weapon. If you look at the front, there are three holes, there was a bullet in each hole and here is the trigger. This is currently loaded and dangerous, two bullets remain."
The third bullet had been fired by investigation authorities to test the weapon. It was accurate and deadly. The would-be assassin who was carrying these devices was arrested on his way to kill his target.
That target was anti-North Korea activist, Park Sang-hak, who has since been given round-the-clock police protection by South Korean authorities. We showed Park the footage of the weapons intended for him. He was shocked. "You'd notice a gun, but these weapons are so innocuous, you can easily kill someone, I'd be dead immediately."
Park says he will continue to send anti-Pyongyang propaganda leaflets across the border in balloons, a practice which has angered the regime, sparking threats of military retaliation. He was aware he was at the top of North Korea's hit list.
It was at that meeting Ahn was believed to have planned to kill Park, according to South Korean authorities. Ahn was convicted in April and sentenced to four years in prison.
"I didn't believe they'd try and kill me on the crowded streets of Seoul, I thought the NIS was over-reacting," Park said. He now knows they saved his life but is also convinced that it will not be the last attempt on his life.