At the instigation of Catherine an unsuccessful assassination attempt was made against Coligny on Aug. 22, 1572, in Paris. Charles visited him, promising a full investigation. Catherine, knowing that she would be discovered, played on her son's fears and instabilities by telling him that the Huguenots were plotting to retaliate against him. In an outburst of rage, Charles ordered the deaths of the Huguenot leaders, including Coligny, and the massacre of St. Bartholomew's Day began.