All's fair when love is war.

When successful financial advisor Derek Charles (Idris Elba) settles into a new Los Angeles neighborhood with his loving wife Sharon(Beyonce Knowles) and young son Kyle, everything seems perfect. But when a beautiful temp, Lisa (Ali Larter), joins the firm, Derek's life takes a strange turn. After a misunderstood encounter at the company holiday party, Lisa begins to spiral out of control - putting Derek's career in jeopardy and Sharon's marriage and life on the line.