It's the rental version - but don't worry, everything from the retail version is here too.
Homicide detectives Cassie Mayweather (Sandra Bullock) and Sam Kennedy (Ben Chaplin) are called in to investigate a murder, and soon find clues that point to school caretaker Ray (Chris Penn). Cassie then goes to Ray's house to look for further clues, but is violently attacked by his pet baboon and hospitalised. Upon her recovery, Cassie discovers that the case has been closed and that Ray is now dead, apparently having committed suicide. Nevertheless, despite what her colleagues say, Cassie is convinced that justice has not been done, and resolves to get to the bottom of the matter.