Helix

Peter Farragut, Sarah Jordan and Dr. Kyle Sommer go to a mysterious island to investigate an unknown pathogen that killed everyone, except Leila, aboard the Mist of Avalon.

Jordan discovers Alan, Peter's brother, is a member of Brother Michael's cult, but despite Alan's warnings she and Peter refuse to leave the Abbey and continue to investigate how Soren became infected.

Peter and Jordan leave the safety of the Abbey to retrieve some specimens and discover just what's living in the woods, meanwhile Sister Amy plots to make them leave forever.

Michael tries to maintain control over his Sisters and the Abby while Alan becomes increasingly suspicious about Peter's real motivation for being there.

Peter reveals his brother's secret and gets them both in trouble, meanwhile Kyle has his hands full trying to quarantine the orchard and the infected hive.

Walker learns about Michael and decides to go St. Germain, meanwhile on the island things are going from bad to worse.

The Coast Guard arrives on the island to take the CDC team to another island to deal with another outbreak of the pathogen, meanwhile Sister Amy has to contend with Brother Michael and his plans.

Walker and Balleseros arrive at the Abbey while Alan, Kyle and Winger are out in the woods searching for the tree with red sap that might be a cure for the pathogen.

At the Abbey Sister Amy makes a bargain for immortality, while in the woods the race is on to find the Bleeding Tree now that Kyle is infected.

Walker prepares to implant Jordan's baby into Amy while the Navy prepares to implement Plan B, a final solution to ensure the virus and all infected people never leave the island.

While Kyle and Jordan try to escape the island as the followers hunt them, Walker and Alan search for the Mother Tree so that Walker can halt ILARIA's deadly plan.

The past, present, and future collide as everyone's paths take some unexpected and tragic - turns.