Related Clues:

• Make secret garden, almost penetrated by officer
• Almost finished penning military leader's cipher
• Convert words into code
• Make safe from data thieves
• Create cryptograms
• Camouflage, as a message
• Starts to engage underground cell to put messages into code
• Make hard to read, in a way
• Scramble data for company in dire need
• Don't make a message plain
• Require decryption to read
• Officer in the first place briefly to turn to Morse?
• Create a cipher
• Use an Enigma machine, say
• Make tough to make out