In the 2150's, a scientist discovers time is actually fluid; past, present, and future all exist at the same time. What he doesn't know, is if the current timeline can change when something is changed in the past. The US government wants him to find out. The theme being to make right what once went wrong.
Unfortunately, a group of time travelers from 50 years in the future are determined to stop the scientist from changing the past. So, they steal the spaceship Einstein, which has the time device on board, causing them to end up in 20th century Earth, which sets up a time loop until the scientist and his group break it by beginning their missions. When they end up back in their present time, they find things have changed, but not necessarily for the better. Will they return to the point in time where everything changed, or will they decide they've messed with history too much? Find out in this time travel novella.