Agent "La Guillotine", known to her colleagues as the "Bye-Bye Girl", wrote her codes in much the same way as her victims met their demise.

Her favourite quip was: "I like the finale of my jobs gift wrapped in nothing, even the petite!"

From her superior came this message:

4 D ô ä õ E 4 U d U % t • D … D □ $ t U E ” U @

Translated to ascii that reads:

52, 68, 244, 228, 245, 69, 52, 85, 100, 85, 37, 116,
149, 68, 133, 68, 21, 36, 116, 85, 69, 148, 85, 67

With the potential of another victim what was she advised?

The Ascii 21 which is a 'control' character does not show and has been represented by a small square, unicode 25A1.