What is In the soup?
In the soup definition and meaning on Dictionary terms:
a liquid food made by boiling or simmering meat, fish, or vegetables with various added ingredients.
Slang. a thick fog.
Slang. added power, especially horsepower.
Photography Slang. developing solution.
soup up, Slang. to improve the capacity for speed or increase the efficiency of (a motor or engine) by increasing the richness of the fuel mixture or the efficiency of the fuel, or by adjusting the engine. to give spirit or vivacity to; enliven: a political rally souped up by the appearance of the candidates.