After a man's family dies in what appears to be a murder, he gets a phone call from one of the dead, his niece. 
 
This film seems to have a similar premise to the movie entitled Frequency (2000), starring Jim Caviezel and Dennis Quaid:  Where a son in the current time period has the ability to save his father 30 years in the past with the use of a ham-radio.
 
FUN FACT:  This film is the third time actors David Oyelowo and Storm Reid have worked together. Previously they were both in Jay-Z feat. Beyoncé: Family Feud (2017) and A Wrinkle in Time (2018).