At will and Red-handed

At will adverb - As one chooses or pleases.

Red-handed and at will are semantically related. In some cases you can use "Red-handed" instead an adjective phrase "At will".

Red-handed adjective - In the act of committing a crime or other reprehensible act.

At will and red-handed are semantically related. Sometimes you can use "At will" instead an adjective phrase "Red-handed".