'Turpitude' was a British deception element of 'Zeppelin' (i) comprising the fiction of a build-up of strength in northern Syria as an encouragement to Turkey to take a strong line against German blandishments (May/26 June 1944).

This was therefore the eastern Mediterranean element of 'Zeppelin' (i) and designed to complement 'Vendetta'. As such, the undertaking promoted the 'story' that the British were planning to make an amphibious landing at Thessaloníki in northern Greece and then advance up the valley of the Struma river to effect a link with Soviet forces which were to have landed at Varna in Bulgaria before thrusting inland. The 'story' also included the development of preparatory facilities in Turkey and a preliminary assault on Rhodes.

Related deception operations were thus 'Vendetta', 'Zeppelin' (i) and 'Dungloe'.

'Turpitude' was the last phase of 'Zeppelin' (i) and designed to suggest that, with landings in Crete and the Peloponnese cancelled, the only operation to be undertaken in the eastern Mediterranean by by the forces of General Sir Henry Maitland Wilson, the Supreme Allied Commander Mediterranean, was to be the capture of Thessaloníki one Greek infantry division and two British armoured divisions passing through Turkey into Thrace, followed by an advance up the valley of the Struma river to link with the Soviet forces in Bulgaria. Turkey was to be entered on 1 June or thereabouts in the aftermath of an ultimatum to be delivered immediately after the notional Soviet landing at Varna, and another infantry division, with air cover from Turkey, was to land on Rhodes in August.

'Turpitude' was planned by 'A' Force in Cairo, largely by Major Michael Crichton, and undertaken largely by the headquarters of Lieutenant General W. G. Holmes’s British 9^th Army, the garrison force for Palestine and Syria, and by the RAF. Major Victor Jones brought his 'brigade' of dummy vehicles from Cyrenaica to represent the fictitious 20^th Armoured Division, which then 'joined' Major General R. H. Wordsworth’s real Indian 31^st Armoured Division near Aleppo in Syria, while a substantial array of real and dummy anti-aircraft guns and aircraft was created in the same area. As the same time a programme of road-building, stockpiling, fake radio traffic and an assortment of other activities made the northern part of Syria a 'hive of military activity' until the operation was ended from 26 June.
As of 6 July, with 'Vendetta' and 'Turpitude' closed, 'Zeppelin' (i) came to an end.

'Zeppelin' (i) and its various sub-operations had been nicely conceived as they played directly to German fears, evident right from the start of 1944, about the eastern part of the Mediterranean theatre. Instructions forwarded to Generalfeldmarschall Maximilian Reichsfreiherr von Weichs, the Oberbefehlshaber 'Südost' in the first days of January had warned that Allied emphasis on a cross-Channel assault might actually be cover for a main offensive in the Balkans. Throughout January, Oberst Alexis Freiherr von Roenne of the Fremde Heere West expressed his concerns about Allied intentions toward the south-eastern part of Europe. Over the next few months, however, it became clear that Turkey would not enter the war, and during March the closing phases of the Soviet 'Dniepr-Carpathian Strategic Offensive Operation' in Ukraine and the opening of an offensive by Josip Broz Tito’s partisan forces in Yugoslavia diverted German attention and persuaded von Roenne, if only briefly, that if the Allies had not struck at this highly opportune moment there was little likelihood of major
Allied operations in the region. But by April von Roenne was worried once more, and in May the operations staff of Generaloberst Alfred Jodl at the Oberkommando der Wehrmacht, working on the basis of von Roenne’s order of battle for the western Allies, came to the conclusion that the Allies must be preparing an invasion of Greece, Albania and the islands of the Aegean Sea using 14 divisions or divisional equivalents.

This reveals that 'Wantage' and 'Zeppelin' (i) had worked, at least of a significant degree. Although 'Vendetta' was not as effective as 'Fortitude South', the Germans did note the preparatory moves laid on for their benefit in North Africa. But to the extent they took it seriously, for they suspected that much of the preparatory effort was indeed of the deception type, they believed that the target might be Italy or the French Riviera rather than the area of Sète farther to the west on the south coast of France.