The political career of Marcus Tullius Cicero began in 75 BC with his election to the office of quaestor, and ended in 43 BC, when he was assassinated upon the orders of Mark Antony.
 Cicero, a Roman statesman, lawyer, political theorist, philosopher, and Roman constitutionalist, reached the height of Roman power, the Consulship, and played a critical role in the transformation of the Roman Republic into the Roman Empire.
 A contemporary of Julius Caesar, Cicero is widely considered one of Rome's greatest orators and prose stylists.
Lucius Sergius Catilina, known in English as Catiline ( ; 108–62 BC), was a Roman Senator of the 1st century BC best known for the second Catilinarian conspiracy, an attempt to overthrow the Roman Republic and, in particular, the power of the aristocratic Senate.
 He is also known for several acquittals in court, including one for the charge of adultery with a Vestal Virgin.
Publius Nigidius Figulus (c. 98 – 45 BC) was a scholar of the Late Roman Republic and one of the praetors for 58 BC.
 He was a friend of Cicero, to whom he gave his support at the time of the Catilinarian conspiracy.
 Nigidius sided with the Optimates in the civil war between Julius Caesar and Pompeius Magnus.
Marcus Antonius (Latin: ; January 14, 83 BC – August 1, 30 BC), commonly known in English as Mark or Marc Antony, was a Roman politician and general who played a critical role in the transformation of the Roman Republic from an oligarchy into the autocratic Roman Empire.
The personal life of Marcus Tullius Cicero provided the underpinnings of one of the most significant politicians of the Roman Republic.
 Cicero, a Roman statesman, lawyer, political theorist, philosopher, and Roman constitutionalist, played a critical role in the transformation of the Roman Republic into the Roman Empire.
 A contemporary of Julius Caesar, Cicero is widely considered one of Rome's greatest orators and prose stylists.
The first Catilinarian conspiracy was a plot to murder the consuls of 65 BC and seize power.
 Historians consider it unlikely that Catiline would have been involved in the first Catilinarian conspiracy or, indeed, that the conspiracy existed at all.
Publius Cornelius Lentulus, nicknamed Sura, (114 BC – 5 December 63 BC) was one of the chief figures in the Catilinarian conspiracy and also a stepfather of Mark Antony.
Catilinarian conspiracy or Catiline conspiracy may refer to:
The writings of Marcus Tullius Cicero constitute one of the most famous bodies of historical and philosophical work in all of classical antiquity.
 Cicero, a Roman statesman, lawyer, political theorist, philosopher, and Roman constitutionalist, lived from 106 to 43 BC.
 He was a Roman senator and consul (chief-magistrate) who played a critical role in the transformation of the Roman Republic into the Roman Empire.
 A contemporary of Julius Caesar, Cicero is widely considered one of Rome's greatest orators and prose stylists.
The second Catilinarian conspiracy, also known simply as the Catiline conspiracy, was a plot, devised by the Roman senator Catiline, with the help of a group of fellow aristocrats and disaffected veterans of Lucius Cornelius Sulla, to overthrow the consulship of Marcus Tullius Cicero and Gaius Antonius Hybrida.
 In 63 BC, Cicero exposed the plot, forcing Catiline to flee from Rome.
 The conspiracy was chronicled by Sallust in his work The Conspiracy of Catiline, and this work remains an authority on the matter.

Question: How was one of the cheif figures of the Catilinarian conspiracy connected to a general who played a critical role in the transformation of the Roman Republic?
Answer: stepfather