The six soldiers flew from Derna airfield on 27 May 1943 and parachuted to Black Lake in Montenegro at the height of a large German offensive Operation Schwarz which aimed to destroy the Partisan forces.
The selection of targets varied, from disrupting German supplies to North Africa by cutting off the railway line to Greece to shipments of Romanian oil and Yugoslav minerals (e.g. copper, chrome and bauxite) to Germany.
[4] Deakin and the team followed Partisan HQ across the Durmitor range ending up in German, Italian and Bulgarian encirclement under heavy bombing.
On 11 September 1943, Deakin, together with an American Capt M Benson left for Bugojno, to join Gen Koča Popović and the 1st Proleterian Brigade on their way to Split.
[11] After a brief speech to the citizens of Split in the main square, translated by Ivo Lola Ribar, Deakin and Wroughton returned to Jajce via Sajkovići, Grahovo and Drvar.
The new commander, heading his own Maclean Mission (Macmis) felt that Deakin, after three months at Tito's HQ "should give us a better idea than anyone of what the partisans were worth".
[14] Maclean left Jajce for Cairo on 5 October 1943 where he presented Anthony Eden with a written report of his views and findings, before returning to Italy to organise the evacuation of Ribar and Milojević from an improvised airstrip at Glamoč.