Castor and Topside force Sarah to make uneasy alliances

Sarah, Felix, and Mrs. S take a trip hoping to track down the Castor Original

When Rachel makes a promise to Sarah, it comes with a hefty price

Alison tries to take her and Donnie’s business to the “next level”

Felix presses Rachel for information about Sarah’s whereabouts

Helena and her seestra are reunited at the Castor camp when Sarah is captured

Sarah’s fate hangs in the balance as she tries to save her sister

A shocking revelation about the Castor-Leda connection has the sisters reeling

Castor pursues the Leda clones for original tissue samples

The menace of Castor rears its head once more