Short answers, pulled from the story.
The Coup of 18 Fructidor was a seizure of power in France carried out on the 4th of September 1797, when members of the Directory annulled election results and expelled royalist deputies from the legislature. Three Directors, Paul Barras, Jean-François Rewbell, and Louis Marie de La Révellière-Lépeaux, staged the action with military support.
The coup was triggered by the April 1797 elections, which gave royalists and moderate republicans a majority in both chambers of the legislature. The new majority repealed laws against non-juring priests and emigres and forced out Jacobin ministers, prompting the republican Directors to act before a monarchy could be restored.
Napoleon Bonaparte supplied documentation of General Pichegru's pro-royalist activities to the republican Directors, giving them grounds to accuse the legislature of plotting against the Republic. He then sent troops under General Charles-Pierre Augereau to Paris to support the coup.
214 deputies were arrested following the coup. Of those, 65 were subsequently exiled to Cayenne in French Guiana, including Pichegru, Ramel, Barthélemy, and Carnot. Election results in 49 departments were also annulled.
Jean-Charles Pichegru was President of the Council of Five Hundred and was widely believed to favor a restoration of the monarchy. He was arrested on the 4th of September 1797 and was among the 65 deputies subsequently exiled to Cayenne in French Guiana.
Around 1,320 priests accused of conspiring against the Republic were deported following the coup. Additionally, 160 recently returned emigres were sentenced to death.