The Serbian army has retreated into Albania to escape destruction at the hands of the German, Bulgarian and Austro-Hungarian invaders of their country. Many of the Serbian soldiers and the civilians fleeing with them have died crossing the Albanian mountains, mostly from exposure and the effects of hunger but some at the hands of Albanian raiders; many Albanians are less than pleased at the Serbs bringing the war into their country.
The Serbs are making their way to the coast, where they hope to be brought to safety by Allied ships. To interfere with this evacuation an Austro-Hungarian naval force headed by the Helgoland sails down into the Adriatic to attack the Albanian port of Durazzo, now under Italian occupation (and renamed from the Albanian Durrës). On their way they spot and sink a French submarine. Then they bombard Durazzo and sunk some Greek ships that may have been planning to assist the Serbs. Then their luck runs out as they blunder into a minefield. One Austro-Hungarian ships is sunk, another, the Triglav severely damaged.
The Austro-Hungarians now decide that discretion is the better part of valour and begin to retreat back to base, towing the crippled Triglav. But there is danger ahead for the slow-moving flotilla. British, French and Italian ships are converging, intent on destroying the Austro-Hungarian squadron. They race northwards hoping to catch the enemy ships before they reach safety.
SMS Helgoland (Wikipedia)