"Lt." Eva conspicuously wears the rank insignia of a Staff Sargent.
The Soviets try to eliminate Einstein before he can help the Alliesby creating weapons that far surpass the Soviets. But what the Soviets don't know is that Einstein is what also created the time machine (which he used to eliminate Hitler before he formed the Nazi party and thus triggered the European theater of World War 2), so eliminating him would create a time paradox and thus would erase even the soviet created time machine.
As the Soviets time warp back to 1927, they see Einstein who looks like he is 70 years old. In reality Einstein would be either in his 40's or his 50's by the 1920's.
This is supposed to be a time where Einstein does not exist long enough to create atomic and nuclear weapons, but yet the Soviets were able to create megaton bombs.