Though WWIII is on the horizon, Okabe attempts to live a normal college life. However, a newly developed AI is about to shake up his world.

After a chance encounter with Maho where they discover knowing someone in common, Okabe has his first face-to-face with her special AI, Amadeus.

Mayuri tries to bring everyone together for a Christmas party at the lab, but Okabe has a rude awakening.

While Okabe is left with more questions than answers, Suzuha recruits help in her search for an unexpectedly close person.

Their search continues as New Years swiftly approaches, though Ruka's dilemma with a certain guest might make matters worse.

Now that the girl's identity is known, Okabe and friends kick off the New Years with a shrine visit and party to never forget.

As Okabe seeks answers regarding the attack, trouble with Amadeus brings a surprising turn of events.

Okabe is given a bittersweet reminder that in changing world lines, sacrifices must be made.