“Stakeout” (** out of four) was a cold-hearted thriller about a struggling young private investigator (Jeremy Sumpter) who tries to help a young woman (Amber Sweet) to commit fraud in order to help his dying mother but finds out too-little/too-late that he’s been doublecrossed and has to try to sort out the mystery and clear his name on the seamier side of L.A. Promising beginning has some sharp dialogue and observations about life in detective work but it soon stalls about halfway through and never rises above the mire and film’s ending is unsatisfying and flat. Tom Berenger adds some style as Sumpter’s burned out father. Originally titled “Sargasso” and based on the real-life experiences of writer/director Adam Sigal who himself was a former P.I.