It's time to pull out your favorite Sonic-Screwdriver/Lightsaber/Wizard's Staff and hop into your Police-Box/Delorean/Phone-Booth, because this puzzle is going to require geeky knowledge and accurate time-jumping skills!
Your friend Ray Adams has forgotten his computer password, and without it he won't be able to access the latest draft of his next novel, "Celsius 42". He needs to get the draft to his publisher soon, or else! All he has to help him remember his password is a scrap of paper with a brief message and a jumble of letters and numbers:
Remember, your password is a perfect length-
Can you decipher Ray's password to get him into his computer?
Ray is notorious for his inefficiency in encoding messages, but is also consistent. Each plaintext character results in the same number of ciphertext characters.
Most of the sci-fi references in this puzzle are just flavor-text, but if you need help understanding them, I'm sure Puzzling's sister site could help.
The first paragraph says that you'll need accurate time-jumping skills. To be more precise, you'll need to be able to time-jump to specific points in the past with down-to-the-minute accuracy.
Ahem, even if you do already understand all of the references, perhaps it would be a good idea to browse some of the highest voted questions and their answers on the Science Fiction and Fantasy Stack Exchange.