Actor Jason Isaacs makes us quickly forget his villainous role as Lucius Malfoy in the Harry Potter saga and instantly root for him as the detective Michael Britten who, after a mysterious car accident, is experiencing his day-to-day life in two separate realities -- one in which his wife died and his son survived, and the other in which the reverse happened. The rest of the cast is equally enthralling -- Laura Allen as Michael's beautiful wife Hannah and Dylan Minnette as their son Rex.
The show does a fabulous job of raising questions while keeping the plot moving and the pace brisk. Is Michael suffering from trauma and dreaming one or both realities? The cinematography presents each parallel plotline with a different subtle color scheme -- red and blue/green. At one point during the pilot episode, it abandons the color differentiation, making us feel the confusion of Michael as he wakes up unsure of which reality he's experiencing and panicking that maybe he's in a version where both his wife and son might be gone from his life.
Each reality has slight disparities -- Michael is seeing a different therapist in each "lifeline," Dr. John Lee (played by B.D. Wong) in one, and Dr. Judith Evans (played by Cherry Jones) in the other. Wilmer Valderrama is a uniformed police officer in one reality and Michael's detective partner in the other. (The great actor Steve Harris plays Detective Isaiah "Bird" Freeman, Michael's partner in the alternate state of events.) In the first episode, Michael solves two separate crimes, one in each waking life, with clues obtained from each one.
It's a fascinating premise. I hope the showrunners have an answer to the mystery and aren't just making it up as they go along. If they can continue the excellent storytelling, it should be fun to see how it plays out.