I need to think of a better title, so if you've got any suggestions, I'd love to hear them.
In 2019 Aliens come to Earth and demand our surrender. We are now advanced enough technologically to be a threat to them, so either we join them as a slave race, or we are beaten into submission. Within hours the governments of the world come forward with information they think will give humans hope. They have been able to prove scientifically since the 1930s that humans have superpowers, but that the brain restricts them so that we don't burn more calories. This is believed to be a mutation that originated in the ice age, as the food shortages made it quite beneficial to have the mutation that causes area of the brain which prevents us from having powers. The government had discovered that by removing this area they could allow people to develop powers. Every powerful government in the world had a program to exploit this fact. There were three ways they could do it:
1) Toxin designed to damage the area of the brain which prevents powers. Often causes damage to other areas, though. Powers start off weak and grow slowly every time the chemical is administered.
2) Surgery removes the area. Can cause some damage to surrounding tissue depending on the skill of the surgeon. Also, powers start off strong and then grow, unlike method one, so those that use this method have less control.
3) Gene therapy. This meant that either the person had to grow up before they were useful to you, or you had to use it on an adult, which decreased the time they had to learn, and their powers grew slowly for the next several years as their brain was altered.
We are either people who have one of these three methods used on us after the announcement, when they start recruiting people to fight the aliens, or the people the governments experimented on. The second group will be much stronger, but emotionally, and mentally unstable, plus they may have other brain damage.