Based on the internationally best-selling series of books by Lemony Snicket and starring Emmy and Tony Award winner Neil Patrick Harris, A Series of Unfortunate Events recounts the tragic tale of the Baudelaire orphans -- Violet, Klaus, and Sunny - whose evil guardian Count Olaf will stop at nothing to get his hands on their inheritance. The siblings must outsmart Olaf at every turn, foiling his many devious plans and disguises, in order to discover clues to their parents' mysterious death.
After the three young Baudelaire siblings are left orphaned by a fire in their mansion, they are carted off to live with their distant relative, Count Olaf. Unfortunately, Olaf is a cruel, scheming man only after the inheritance that the eldest Baudelaire Violet is set to receive. The children escape and find shelter with their quirky Uncle Monty and subseqently, their phobic Aunt Josephine, but Olaf is never far behind.
Following the sham wedding ceremony, Olaf manages to escape while the Baudelaire siblings are sent to live with their herpetologist uncle Dr. Monty Montgomery, who has come across a reptile known as the "Incredibly Deadly Viper". While attempting to learn more about Montgomery, a skeptical Klaus discovers that the hedge maze is the same shape as the tattoo on Olaf's ankle. Olaf poses as Montgomery's new assistant in an attempt to kidnap the siblings, but Montgomery receives a encrypted message at the last minute and buys the children tickets to Peru. Believing Olaf to be a spy sent to steal his research, Montgomery tells him to leave.
After dismissing Olaf, Montgomery notices that the door to his Reptile Room is ajar and investigates only to be attacked. The following morning, the Baudelaire siblings discover Olaf standing next to Montgomery's corpse. Olaf forces them to accompany him to Peru, but is prevented from carrying out his plans when Mr. Poe appears to check on them. When the police determine that the "Incredibly Deadly Viper" killed Montgomery, the siblings successfully prove the viper's innocence and unmask Olaf. Olaf escapes via the hedge maze as the siblings are confronted by a mysterious woman who tells them to find Aunt Josephine.