Nero Wolfe (2001) 2x1

A simple favor for a friend leads Archie to a dead body. The friend is arrested but Wolfe suspects the real murderer is still on the loose, though Archie isn't so sure. His investigations take him to the victim's sister, who is willing to go to any length to keep her sibling's transgressions a secret. Only a clever ruse by Wolfe finally flushes out the killer.