At the time, Captain Sadoul was in Germany, returning to Moscow in 1921 on the same convoy as Radek, Enver Pasha, Curt Geyer and Paul Levi. In 1922, reinstated by the Comintern, he was admitted into its Executive Committee. Sadoul was also a defender of the Socialist Revolutionary Party's "second group" in the Moscow show trial, a last-minute replacement for Antonio Gramsci. Like Serge, he felt emotional about the demise of "this peasant Party of significance", his intervention ensuring that no SRs were executed. In September, Sadoul prepared for a trip to Ankara, where he was supposed to reestablish the Turkish Communist Party. The plan fell apart when Mustafa Kemal issued a warning for the Comintern not to get involved. Around 1923, he was again in Berlin, at Grunewald, playing host to Serge and Nicola Bombacci. During that interval, the White émigré paper "Dni" alleged that Sadoul had squandered the 1.4 million chervontsev that the Comintern had provided for stirring up revolt in the French colonial empire. From abroad, Sadoul published in the PCF's "L'Humanité", condemning the occupation of the Ruhr as a ruse by the French industrial lobby. His other articles, outlining the core ideas of the "united front" strategy, were circulated by Longuet at the SFIO Congress of 1923, and taken as proof that the PCF was to be mistrusted. The PCF intended to present Sadoul and Guilbeaux as its main candidates in the May 1924 elections, but the authorities censured this move; the communist list was consequently changed to include Hadjali Abdelkader, an Algerian independence militant. The election marked a decisive victory for the left-wing alliance, Cartel des Gauches. Rather than promising social reforms, the Cartel focused on symbolic causes, including amnesty for Sadoul, which was also one of the PCF's key demands. On December 3, Sadoul reentered France through Belgium, just as Prime Minister Édouard Herriot was contemplating the normalization of relations with the Soviet Union. He was welcomed in the home of industrialist Albert Vidal, who had been his friend since before the world war. Following a stakeout, the "Sûreté" arrested Sadoul in Paris (where he was visiting the PCF's Jacques Doriot), and dispatched him to Cherche-Midi prison.