It's Just a Poisonous Fish in the Courtyard, How Can It Become an Enemy Agent?

[Siheyuan + Space + Mild Violence + Toxic Science Popularization + Joining the Army + Cool Writing + Foreign Single Female Protagonist] Zhao Jun, a post-00s graduate majoring in animal and plant quarantine, accidentally fell off a cliff in Huashan Mountain and traveled to the world of "Love in the Courtyard". The beginning was the difficult situation of shouting under the flagpole in front of Tiananmen Square, "I'm just a poisonous fish, I'm really not an enemy agent." What's even more shocking is that he discovered that he was summoned after the previous "Zhao Jun" who parachuted through time was obliterated by Heaven and the system dissipated. Unwilling to bear the burden of three people, one person started in the 1950s and embarked on a unique and exciting career!