It was misty and rainy in Jiangnan in June, and suddenly there was a sound of footsteps in the quiet alley. When I looked up, I saw a man in military uniform and leather shoes, carrying something in one hand and a letter in the other, slowly walking towards the alley. .

Finally, the footsteps stopped in front of an antique wooden door. The man picked up the letter and carefully compared the house number on the wooden door before reaching out to knock on the door.

After ...