He was serving as Executive Officer of the USS Pope DD-225 which was sunk by the Japanese. He was the senior officer among the 150 members of the crew who survived the sinking and assumed command of the group. He organized the men and carefully distributed the meager remaining rations. Under his direction, all of his command survived until a Japanese destroyer pulled them from the sea a week later.

They were then taken to a prisoner-of-war camp at Makassat on the island of Celebes. Like all prisoners of the Japanese, they found themselves at the mercy of sadistically cruel prison guards. Because the Japanese military culture permitted no surrender, they considered their Allied prisoners to be subhuman for having been captured.  Beaten or tortured for the slightest infraction of the camp's many petty rules, the POWs lived in constant fear of their guards.

One day in April 1942, a Naval officer broke one of the rules when he failed to bow low enough to a guard. Infuriated at this supposed insult, the guard went into a frenzy. Grabbing his swagger stick, he began beating the officer. Again and again the club swung through the air, tearing human flesh.

Antrim, watching the beating with the other prisoners, finally had enough. In the preceding weeks he had seen too much cruelty, too much needless death. Something had to be done to halt the carnage. "Stop," he commanded, stepping forward. Later, he wasn't sure who was more stunned at this bold move, the guards or the other prisoners. By using Pidgin English and sign language, he convinced the guards to discuss the charges against the officer, now huddled nearly unconscious at their feet.

Soon the entire Japanese prison force assembled in the open yard of the compound. The 2,700 Allied prisoners stood silently by, unable to believe the events enfolding before their eyes. Antrim argued the officer's case to the Japanese.  The officer meant no insult, he told them. He explained that Americans were not used to bowing. They needed more time to learn Japanese customs. The camp commandant was unmoved by his pleas. With the prisoners waiting nervously, the commandant ordered the officer punished with 50 lashes. Fifteen blows with a length of heavy rope rained down on the man, driving him into unconsciousness. Three of the enlisted guards, intoxicated by the now-bloody body before them, began kicking the downed officer along the ground. Antrim was unable to control his fury and disgust.  He stepped forward again and, in a bold, clear voice, he said, "I'll take the rest." Stunned silence fell over the entire compound.

The Japanese were amazed at Antrim's maneuver. He repeated the offer, "I'll take the lashes." At that moment a robust, spontaneous roar erupted from the assembled prisoners. His actions were the bravest they had ever witnessed. The Japanese didn't know what to do.  After considering among themselves, the commandant indicated that the unconscious officer could be carried to the dispensary.  He then bowed slightly to Antrim, saluting him for his willingness to sacrifice his own life for another's. The POWs again roared their approval. His actions did not completely end the Japanese cruelty at the camp, but they did earn the POWs a respite from the senseless beatings, as well as bringing them a new respect from their guards.

A native of Peru, Indiana, Antrim had entered the United States Naval Academy in 1927, graduating in 1931. Commissioned as an Ensign he then undertook a series of routine shipboard assignments over the next 9 years. In 1940, he had the unusual distinction of qualifying as a dirigible pilot. He then joined the USS Pope as Executive Officer.

Once that the POWs were liberated in September 1945, his gallant conduct quickly became known. The Medal of Honor was presented to him on January 30, 1947. He had already been awarded the Navy Cross for heroism prior to the time that the USS Pope was sunk. He remained on active duty until ill health caused by his years as a POW forced his retirement in April 1954 as a Rear Admiral. He died on March 8, 1969 at Mountain Home, Arkansas, and was buried in Section 35 of Arlington National Cemetery.