In 2010, Mari Gilbert’s (Amy Ryan) daughter does missing in Long Island, New York. Frustrated by the police inaction she starts her own investigation into the disappearance that results in the police discovering more dead women buried in the region. 

Lost Girls is based on the novel Lost Girls: An Unsolved American Mystery by Robert Kolker which is based on the murders of the unknown Long Island serial killer. This film focuses firmly on Mari Gilbert’s campaign to have her daughters case taken seriously by the police and the possible people who may have been responsible. 

Even without an answer to the mystery films like David Fincher’s Zodiac have provided incredibly compelling and entertaining films. Lost Girls manages to only maintain this interest for the first half of its running time when it is following a searing performance from Amy Ryan trying to get the police to take notice. When the film switches to the action, or lack there of by the police or possible suspects it loses all of its initial interest and tension. At this point it becomes a little scattershot as we meet other relatives of victims, a few different suspects and are then treated to a “one year later” coda. 

Thomasin McKenzie and Gabriel Byrne give Ryan good support as her middle daughter and the police commissioner responsible for the case. 

An interesting subject that does not quite hold the attention for its full duration.