Operation Hydra was a failed British attempt during World War II in Yugoslavia to develop contact with the Partisans led by Josip Broz Tito, in Montenegro in February 1942.
Two British Special Operations Executive agents and an officer of the former Royal Yugoslav Air Force were put ashore at Perazića Do, just north of Petrovac.[1]
On 4 February the three agents went ashore from the British submarine HMS Thorn. They were Major Terence Atherton (a former journalist and agent in Belgrade), Lieutenant Radoje Nedeljković of the Yugoslav Royal Air Force and Sergeant Patrick O'Donovan, wireless operator.
Their orders were not to contact Draža Mihailović, or to locate SOE agent Duane "BIll" Hudson, who had been out of radio contact for over two months. Instead, Atherton was to "to establish a safe area on the coast near Petrovac to which supplies and a further mission or missions could be sent...the original operation order had expressly forbidden the mission to leave Montenegro."[2]
The operation failed completely. The presence of the Yugoslav officer implied links to the royalist Chetniks, which is suggested to have caused Tito to suspect the British of being spies. Nothing beneficial arose, therefore, and the British agents left Tito. They vanished soon thereafter, as did the large amount of gold and Italian money that they carried.
At Mihailović's headquarters Hudson's intervention prompted Mihailović to order a formal inquiry into the fate of the Atherton mission. A summary of the results of this investigation was sent by Hudson to SOE office in Cairo. According to the results of the inquiry, the most probable culprit for Atherton's death was četnik leader Spasoje Dakić.