After more than 25 years of searching, a veteran diver specializing in finding sunken ships has uncovered the location of the HMS Triumph, a World War II British submarine that disappeared in 1942.

Kostas Thoctarides, a renowned Greek diver, and his team located the wreck of the missing submarine at around 670 feet in the Aegean Sea.

Describing the search as “the hardest mission I have ever undertaken in my life,” Thoctarides shared photos and video on social media of the submerged 84-meter T-class submarine, which vanished during a mission against the Axis Powers in January 1942.

The haunting images show sea life growing on every inch of the sunken craft’s exterior after 81 years underwater.

Thoctarides told state news agency ANA that the submarine’s periscopes and hatches were all down, revealing that the vessel was in deep dive during its final moments.

Thoctarides believes that the Triumph was likely in combat with an enemy sub due to the damage in the fore section — and the fact that a torpedo was located “halfway out of the submarine,” with more torpedoes located nearby.

“This fact leads us to believe that the Triumph fired more than one torpedo,” during its last mission, the diver wrote on Facebook.

The HMS Triumph made its maiden voyage in 1938, just a year before World War II commenced, and carried out 20 missions before vanishing.

The sub was charged with attacking Axis ships, as well as delivering British commandos to battle sites and rescuing allied soldiers.

Thoctarides said the submarine departed on its last mission on Dec. 26, 1941, where it left Alexandria, Egypt, on a mission to patrol the Aegean Sea. The craft was then scheduled to return to Britain for repair and maintenance.

The submarine, filled with 55 crew members, seven officers and two commandos, vanished on Jan. 23, 1942, according to records from the British Navy.

The discovery marks the fifth sub Thoctarides discovered in the Mediterranean region, with the diver previously finding the wreckage of the Jantina last year, an Italian submarine that sank in July 1941 after it was torpedoed by a British vessel.