For decades, film lovers have pined for the onscreen coupling of Robert De Niro and Al Pacino. After a tantalizing, 10-minute tease in Heat, Righteous Kill is their first film side by side, an event that should be heralded by angels. Sadly, the film falls far short of the grandeur this pairing deserves.

De Niro and Pacino star as veteran NYPD detectives on the trail of a serial killer whose string of murders circles back to them. Their performances, supported by a dynamic, well-executed script by Russell Gewirtz, shouldn’t be as disappointing as they are. The real fault lies in Jon Avnet’s sophomoric direction that feels better suited to an episode of “CSI” than a feature film.

Grade: C

Righteous Kill is currently in theaters.