The news of King Richard's return to England reaches Robin and the gang - and it means one thing; Marian's marriage to Gisborne is looming closer. Marian attempts to steal Gisborne's money and distribute it to the villagers, Robin tries to find out more about Gisborne's crimes. But then tragedy strikes for the Nightwatchman at Locksley Manor...

In the final episode of the first series, Robin of Locksley mourns the loss of Marian. But in the final fairwells from the group a shocking discovery is made.....

The Sheriff and his sinister scientist, Joseph (pretending to be the Nightwatchman), test a poison, blaming the ill effects on the pestilence.

A horrified Robin realises that his plan to capture the Sheriff's spy, Henry of Lewes, has failed because he has a traitor in his gang. Fearing for Marian's safety in the castle, Robin sets about rooting out the turncoat. His only clue is supplied by Marian: the spy's meeting place is located at the Trip To Jerusalem Inn, where the traitor outlaw sells his secrets to Gisborne.

Prince John's army is summoned to raze Nottingham to the ground at sunset. Gisborne risks his life standing by Marian as they fight to save the townsfolk from oblivion.

The King's guard Legrand arrives with a vital mission for Robin. Robin joins the quest to unravel the coded clues leading to the mysterious Thesaurus Patriae.

Robin and his men battle against Isabella as she rounds up men to send to Prince John. Archer works with his sister and attempts to catch Robin and Gisborne.

Robin and his men are forced to retreat after trying to defend the castle. A final battle sees everyone fighting for their lives.