David, you managed to ruin a perfectly good yarn by not sticking to the twin thing, so lets rewrite it, I will give you the points. George is dead, Steve is in prison, and evil Larry is trying to work his way back into Sara's bed and is still planning to kill her for the inheritance. As we know Larry makes it and the sex is good, Sara wants some more so she goes down on him and horror of horrors he is uncut, George was circumcised early in their marriage, painful sex. She manages to hold it together, over the next few days she finds the photograph of the twin, George's hospital records, the report from the investigators written by Nadia,the connection to Steve, and the murder weapon, Larry is in trouble.
The tower scene, Larry gets Sara there but she is prepared and has the good old recording device, she confronts him, he admits every thing, goes to push her over she side steps him and over he goes, she goes to look over the parapet expecting to see him dead down below but he is there hanging on and grabs her, fighting, he finally falls. Sara goes down to check that he is no more, but in every thriller the bad guy has to die twice, more fighting, a handy brick and Sara applies the coup de grass.