Episode 4
S1, E4: Okabe learns that the only way to decrypt SERN's time travel experiments is to locate an antique computer, and the only way to locate the computer is to outsmart a maid.

S1, E4: Okabe learns that the only way to decrypt SERN's time travel experiments is to locate an antique computer, and the only way to locate the computer is to outsmart a maid.