Brossolette ran a Resistance intelligence hub from a Parisian bookshop on the Rue de la Pompe, before serving as a liaison officer in London, where he also was a radio anchor for the BBC, and carried out three clandestine missions in France.

He committed suicide by jumping out of a window at their headquarters on 84 Avenue Foch in Paris as he feared he would reveal the lengths of French Resistance networks under torture; he died of his wounds later that day at Pitié-Salpêtrière Hospital.

On 27 May 2015, his ashes were transferred to the Panthéon with national honours at the request of President François Hollande, alongside politician Jean Zay and fellow Resistance members Germaine Tillion and Geneviève de Gaulle-Anthonioz.

Brossolette ranked first at the entrance examination to the prestigious École Normale Supérieure; throughout his education held the title of "cacique" which was internally attributed to the most brilliant student, ahead of intellectuals such as philosopher Vladimir Jankélévitch and two years before Jean-Paul Sartre and Raymond Aron.

He worked as a journalist for Notre Temps, L'Europe Nouvelle, the party newspaper Le Populaire and the state-owned Radio PTT but was fired when he violently opposed the Munich Agreement on air in 1939.

After the Armistice, when the Vichy regime forbade him to teach, Brossolette and his wife took over a bookstore specialised in Russian literature at the Rue de la Pompe near Lycée Janson-de-Sailly, where he had attended high school.

By then assuming a pivotal role in the ZO (Zone Occupée) Resistance, Brossolette coordinated contacts between groups such as Libération-Nord from Christian Pineau, the Organisation Civile et Militaire (OCM) and Comité d'Action Socialiste (CAS).

He finally obtained a liaison with London and General Charles de Gaulle when he was hired by conservative Gilbert Renault also known as Colonel Rémy as press and propaganda manager of Confrérie Notre-Dame (CND), by then the most important network in Northern France.

Brossolette created the civilian arm of the BCRAM intelligence service, which became the Bureau Central de Renseignements et d'Action (BCRA), in liaison with the RF section of the British side, Special Operations Executive (SOE).

In a speech at the Albert Hall on 18 June 1943, he famously praised the soutiers de la gloire (or "stokers of glory") in a reference to the fallen anonymous soldiers and resistants.

Brossolette also resumed his newspaper work through a series of articles on France's situation, including one in La Marseillaise considered by many to be the doctrinal founding of the Gaullisme de guerre movement.

This political and social plan, including nationalisations and price controls, inspired the March 1944 Conseil national de la Résistance programme and was implemented after war.

Brossolette's ideas of a Resistance party raised many opponents' fears of a "bonapartian" drift, especially among fellow socialists in London including Pierre Cot and Raymond Aron.

It was recently confirmed that he was identified by a semi-coded report to London from CNR's Claude Bouchinet-Serreules and Jacques Bingen written by the services of Daniel Cordier intercepted at the Pyrenees, tragically self-fulfilling the severe criticism of Brossolette and Yeo-Thomas about the lack of prudence inside the Parisian Délégation générale.

Both Yeo-Thomas and Friang were captured before planned action as many Parisian networks were dismantled following the so-called "Rue de la Pompe affair" (after the location of the Delegation générale) and Pierre Manuel's avows.

From after the war until the late 1950s, Brossolette was considered the main leader of the French Resistance, though many were claimed heroes by their political family (such as Honoré d'Estienne d'Orves by royalists and Gabriel Péri by communists).

Brossolette's fame was helped by his media notoriety before the war on Radio-PTT and on wartime BBC emissions, his networking role that made his name or codename known and remembered over almost every Resistance member in northern France and by flattering early accounts of BCRA's chief Passy in his memoirs although he had also created, through his independent position and sarcastic wit, many enemies among party leaders, Gaullists, communists and even socialists that survived him.

On 21 February 2014, France's President François Hollande announced the transfer of Pierre Brossolette's ashes to the Panthéon with 3 other resistants Geneviève de Gaulle-Anthonioz and Germaine Tillion, as well as a former pre-war Minister Jean Zay.

In France today, Brossolette's name is better known than the man himself or his life achievements, thanks to the great number of streets – nearly 500 out of which 127 in Greater Paris, schools and public facilities bearing it (see below).