\\\"a furtive manner\\\"
\\\"a sneak attack\\\"
\\\"stealthy footsteps\\\"
\\\"a surreptitious glance at his watch\\\"

\\\"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\\\"