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. The time travelers meet all sorts of 20th century icons, from the Titanic to Anne Frank to Roswell to the Apollo 13. However, someone is trying to stop them, and the future may never be the same again.