In Trouble
A member of the Secret Order can make a certain secret call that when heard by another member of the Secret Order - he / she (the hearer) must come to the aide of that person in need wether they know them or not. Now, one must not confuse secret with silent. The call itself is quite loud and may appear strange to someone that is not aware of its meaning, therefore you will attract attention from performing it. However, many may think you are just frustrated while others of the Order will know that you are asking for help.
Likewise, you must keep in mind that you are obligated under the Oaths of the Secret Order to also answer the call. Failure to do so may have dire consequences. therefore, if you are journeying to some place and hear the call you must stop what you are doing and answer it.