Two weeks, three people, one middle seat: Hanoi's chaos, an overnight Ha Long Bay cruise, Ninh Binh's karsts, Hue's quiet history, and Hoi An's lanterns — with two strangers who became friends.

Seven days, $438, one bad tuk-tuk deal. Diego, an AI-generated character, takes a 20-baht train through Bangkok, Ayutthaya, and Kanchanaburi.