The Vow: Season 1

Mark Vicente and Sarah Edmondson, high-ranking former NXIVM leaders, describe the dream and mission of NXIVM to build a better world. Bonnie Piesse, Mark's wife, tells him she's worried about the organization and Keith Raniere, NXIVM's leader and Mark's mentor. Mark wonders how could tools to make a better, more ethical world be misused?

After seven years, Bonnie leaves NXIVM for Los Angeles and tries desperately to get through to Mark, who reassures her all is well. Mark remains loyal to Keith and NXIVM, but a series of phone calls begin to sow doubt within him.

Sarah confides to Mark about DOS, a secret group involving "masters" and "slaves," and struggles in her relationships with NXIVM, her husband and her best friend. Sarah and Mark lament how many members they've recruited and question what to do next.

Mark, Bonnie, Sarah and Nippy strategize with Catherine Oxenberg about how to get her daughter, India, out of DOS, even though she wants to stay. "Jane," India's close friend, describes the appeal of the organization and why she left it all behind.

Catherine believes her daughter is in danger and wants her to come home. When she and the former members are unable to get the attention of the authorities, they approach the New York Times. Meanwhile, Mark reflects on his time at NXIVM.

Sarah, Mark and Nippy contact additional news outlets to provoke outrage and pressure law enforcement to pay attention. Barbara Bouchey, a former board member and early defector, reflects on her time in Keith's inner circle.

After learning that the New York Attorney General's chief investigator is interested in building a criminal case against Keith, Catherine travels to Buffalo to meet with Frank Parlato, creator of the anti-NXIVM blog "The Frank Report," to build a dossier of evidence. Meanwhile, we're introduced to Toni Natalie, one of Keith's former girlfriends, who takes us back to the '90s to share her experiences and the challenges she faced with Keith during the days of his first company, Consumers' Buyline.

As the group gathers evidence for their FBI testimonies, they express their beliefs about how the curriculums of SOP and JNESS, men's and women's groups within NXIVM, reshaped their ideas on gender roles in society and may have laid the foundation for DOS.

Keith hasn't been seen in Clifton Park for weeks, and the team gets a tip on where he might be. Catherine meets with India, who maintains her position. Mark and Bonnie return to Clifton Park for the first time since leaving NXIVM and confront their memories of Keith and the curriculum. Sarah, Bonnie, Mark, Nippy, and Catherine face a shocking development in the case.