A sailor initially too poor to marry Johanna, but returns to London wealthy after his voyage. Todd lures him to the shop and attempts to kill him, but Mark escapes with help. He later returns in disguise to confront Todd and successfully rescues Johanna from the burning building.
Todd targets Mark for murder and robbery.
Mark and Johanna share a deep romantic bond.
Mark and Pearley are trusted fellow sailors.
Nan alerts Mark to Johanna's dangerous location.