A boarding action!

 is a Sunless Sea Story Event.

Trigger conditions
 is automatically triggered in Fallen London if you have the  Presbyterate Adventuress and:  Learning About: The Presbyterate Adventuress = 10 

Story description
A sudden boil of bodies at the rail! While your zailors were sighing over the sights of London, armed foreigners were slipping up the side of the ship. They wear tight-fitting dark uniforms and carry complicated multiplicities of blades. The Presbyterate Adventuress curses apologetically. “Out of time,” she says.