While tracking a young boy with dangerous powers, Dr. Helen Magnus encounters Will Zimmerman, a psychiatric resident who may have what it takes to become her new protégé.

Will Zimmerman is drawn further into Magnus' mysterious world and finds himself confronting his oldest fear. Elsewhere, forces converge on the target of their hunt - including someone from Magnus' distant past.

The origins of the mysterious mutant boy are revealed, as is the relationship between Magnus and her old flame, John Druitt. Meanwhile Ashley Magnus (Emilie Ullerup) seeks out Ernie Watts (Peter Deluise) a weapons dealer and fellow monster hunter - only to find herself in mortal danger.

Helen and Will confront John Druitt with deadly results for a member of the Sanctuary team. Ultimately, Will is forced to choose between his old life and the strange world of Dr. Helen Magnus.

While investigating an ancient crypt on a remote island, Magnus and her team encounter deadly creatures and three women with a mysterious past. Ashley decides to address the issues of her father's existence head-on.

The investigation into the three women found in the crypt continues, confirming Magnus' theory that they are much more than they appear. Ashley's hunt for contraband creatures yields mixed results.

Will falls victim to the three women's growing powers, while Magnus seeks proof of their true identities via a former resident of the Sanctuary. Ashley's luck in her monster hunt begins to run out.

Magnus, Will and Bigfoot defend the Sanctuary against a deadly assault, while Ashley struggles to survive her encounter with a nearly unbeatable foe.

The Sanctuary team must find and stop Kali before the tidal wave could kill millions. Meanwhile, in Mumbai, Will is still fighting for his life.

Will suffers from amnesia regarding the events of his near-death experience, but some unwanted visitors become intent on finding out what is locked in his memory.

The team goes on a routine mission to retrieve an Abnormal and take it to safety. But the mission becomes anything but routine when they are forced to stage a bank heist in order to protect the public from harm.

Nikola Tesla surfaces, sending Helen an SOS from the Colombian Highlands - but Will doesn't think he can be trusted.

Kate gains super-hero-like abilities when an Abnormal attaches itself to her for safe keeping.

Word of a possible werewolf sighting prompts Henry and Will to visit an English psychiatric facility. As they probe a potential connection to Henry's Hyper Accelerated Protean past - and future - Magnus and Tesla investigate the mysterious holographic city.

Magnus responds to an anonymous call for help at an abandoned building. But when she gets trapped inside, she discovers whoever made the call has a very different agenda.

With Adam on lockdown at the Sanctuary, Magnus investigates his connection to Hollow Earth - and Druitt - while being forced to reveal dark secrets about the chaotic origins of the Five.

Will takes command of the Sanctuary while Magnus and Druitt search for a critical artifact in London. Knowing that Magnus's only hope for a cure lies in the secret subterranean city, Will ignores her warnings and releases Adam-Hyde in the hope that he will lead them to an access point for Hollow Earth.

Seeking a gateway to the secret subterranean city, Magnus leads a treacherous mission to Tibet - telling a bitter Adam that he must stay behind while promising to bring back a cure for their radiation sickness. Because of their source blood, Magnus insists that Tesla and Druitt stay behind as well, taking the only shield Tesla was able to construct for herself. The hidden city, however, is rigged with deadly security traps - and death awaits the team at every turn.

Magnus is revived to answer Ranna's questions and soon figures out that despite Ranna's efforts the city is in great deal of trouble and the fall of Praxis could also threaten the surface world however Magnus is able to help. Magnus and Ranna makes an understanding to help and she revives rest of the gang. Magnus manages to save the city with the help from Gregory Magnus meanwhile Will tries to breakdown Adam's plan that can cause huge trouble.

Returning home from an overnight trip, Magnus is stunned to find the Sanctuary in a complete and utter shambles - only hours before a scheduled inspection by a UN Security Team. A bruised and battered Henry only adds to the mystery by claiming that he was attacked by Will.

Looking to share a quiet, "normal" evening out with Abby, Will and his date are abducted en route to the restaurant by a desperate gang leader who faces certain death without their help. Then, upon learning the abductor's identity, Magnus suddenly ceases all attempts at rescue.

Will's transformation has him literally climbing the walls.

Will and Henry's double date goes awry when Magnus tasks them with an Abnormal delivery.

Magnus and Tesla investigate a former Praxian stronghold and unintentionally stumble on vampiric secrets.

Discover Magnus' role in a turning point of World War II history.

A colleague vanishes amid unexplained disappearances in Normandy, France, where Magnus and her team run into a military blockade during their investigation

Helen and Will find themselves in an alternate reality, living as suburban neighbors, who experience unsettling dreams that disrupt their new careers.

Receiving word that a large group of Abnormals has been spotted near a South Dakotan cave entrance, Magnus realizes it's the first wave of Abnormals emerging from Hollow Earth.