Plot summary
Queen Mary survives a difficult birth to a son, thanks to the help of Bothwell and Greer. While Queen Mary is in labour, Lady Lennox manipulates Darnley into taking over the Privy Council and ousting Queen Mary from power. Mary writes to Elizabeth in kinship, asking her to protect her son and accept him as heir to a united Scotland and England. Darnley is mentally unstable due to syphilis; he hallucinates Keira, and flees the castle with his son. Leeza visits French court and revives the conflict between Charles and Henry.
Although Catherine finds a resolution, Charles is determined to kill Henry over Nicole. Queen Elizabeth believes that Ferdinand killed Gideon, and has naval commander Francis Drake ( Richard Fleeshman ) steal a cargo ship heading for Austria. Drake is successful, but is forced to engage Spanish warships, triggering a potential war with Spain. Elizabeth eventually suspects Jane and has her arrested; Jane is Narcisse's spy, and was the one who poisoned Gideon. Luc gives Claude permission to go to Leith, but she returns to court when she discovers that Leith is engaged to someone else.
Credits
Adapted from Wikipedia contributors, Reign season 4. HTML formatting and reference markers removed.