Graciano Bilas was a 42-year-old Filipino laborer originally employed on a plantation in Hawaii. Born around 1889, likely in the Philippines, he spent part of his working life overseas, which was not uncommon during the early 20th century, especially among Filipino men seeking employment abroad after the United States annexed the Philippines in 1898.

Little is known about Bilas’ early life or family background. He was among many Filipinos working in difficult conditions in the plantations of Hawaii, where laborers were often subject to harsh environments, discrimination, and social isolation. There are no records of Bilas having a criminal past prior to the stabbing spree.

In late May 1931, Bilas boarded the RMS Empress of Canada in Honolulu, en route to his home country. The Empress of Canada was a British ocean liner operated by the Canadian Pacific Steamship Company, making trans-Pacific voyages between North America and Asia. Bilas was listed as a steerage passenger, the lowest class of travel aboard the ship, often crowded and with limited access to amenities. He was among many other laborers and low-income travelers returning home or journeying between colonial outposts.

On the morning of June 5, 1931, while the RMS Empress of Canada was in open waters en route from Honolulu to Yokohama, Graciano Bilas launched a brutal and seemingly random stabbing spree aboard the ship.

At approximately 9:30 a.m. (local ship time, UTC+09:00), Bilas engaged in what appeared to be a friendly conversation with a Canadian crew member. Without warning, he stabbed the man with a pocketknife, and within moments, began targeting others nearby, both crew members and fellow steerage passengers.

Panic spread through the ship’s lower decks as Bilas moved quickly through narrow alleyways and steerage quarters, attacking people at random and often from behind. The suddenness and savagery of the violence left little time for defense. According to ship records, at least 29 individuals were injured, including eight Japanese and nine Chinese passengers who were in critical condition as of the next day.

Two men were killed:

• Chan Yue, the ship's chief engineer
• Chan Ching (or Chang Ching), a young Chinese cabin boy

After about 30 minutes of confusion, the crew managed to locate Bilas hiding in the bow of the ship. He was subdued and placed in the ship’s brig under armed guard. Some reports differ on whether he resisted or surrendered, but he was effectively restrained and kept isolated as the ship continued its journey toward Hong Kong.

Upon docking, Bilas was charged with murder. Despite the large number of victims, he was formally charged only with the killing of Chan Yue. The ship's medical officer testified that Bilas was deeply disturbed and incoherent after the attack, exhibiting signs of severe mental illness. He reportedly stood in one position for hours, refused to eat or drink, and appeared disconnected from reality.

During the trial in late June 1931, the court heard that Bilas believed the Japanese passengers were planning to throw him overboard, which may have triggered the paranoid and delusional assault. Medical experts diagnosed him with manic-depressive psychosis, and in July 1931, he was declared criminally insane. Instead of being convicted and sentenced, he was committed to a psychiatric institution in Hong Kong.

No further public record exists of Bilas following his institutionalization, but given his age at the time, it is presumed that he died in confinement.