hugger-mugger

a state of confusion; ritual accompanied by complicated and purposeless activity that obscures and confuses

• “he engaged in the hugger-mugger of international finance”

in secrecy

• “they did it all hugger-mugger”

in utter disorder

• “a disorderly pile of clothes”

conducted with or marked by hidden aims or methods

• “clandestine intelligence operations”
• “cloak-and-dagger activities behind enemy lines”
• “hole-and-corner intrigue”
• “secret missions”
• “a secret agent”
• “secret sales of arms”
• “surreptitious mobilization of troops”
• “an undercover investigation”
• “underground resistance”

act stealthily or secretively