The six-part docuseries covers the disappearance of Christina Whittaker who went missing in 2009.

Relentless follows what happened to the 21-year-old, who was last seen on November 13, 2009, and follows the investigation done by the Hannibal Police and a private eye that the family hired to help find Christina. Each episode is about 45-minutes to an hour and follow Christina's mom, Cindy, in the search for her daughter.

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The filmmaker dives deep into the investigation focusing on documents surrounding what has been found, and where the investigation stands 10-years later. The filmmaker Christina Fontana, meet Cindy back in 2010 when Fontana was doing a different documentary on missing persons. Fontana travels to Hannibal and starts talking with people who last saw Christina and what they remember about the night she disappeared, and when the search started to find her.

In the first episode, Fontana introduces you to Christina's friends, family, and why got so involved with Christina and her family. There are so many twists and turns in this docuseries that will at times shake your head it disbelief knowing that this happened in American's Hometown.

Every Monday there is a new episode that is release, and so far, there are three available to watch on Discovery+. As Fontana gets deeper into the case and follows any leads so can find, she is shocked and in disbelief in what she uncovers. It's really an amazing docuseries that will open your eyes into how a missing person's investigation takes place.

If you have any information on the disappearance of Christina Whittaker, please contact the Hannibal Police Department and follow Help Find Christina Whittaker on Facebook.

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