Original title (FR): Une amie dévouée (A Devoted Friend)

After witnessing the harrowing November 13, 2015 terrorist attacks, Christelle “Chris” Blandin (Laure Calamy) quickly latches onto a community of survivors. Claiming that her best friend Vincent was one of dozens critically injured at the Bataclan Theatre, Chris becomes an indispensable resource for the group but discrepancies begin to pepper her story – raising serious doubts among the true victims of the tragedy.

https://www.themoviedb.org/tv/224011-la-mythomane-du-bataclan