1x4 - Forever Knight

A young woman dies, and all evidence points to suicide. Nick, however, has a gut feeling that it was murder, but seems unable to prove it. Added to his stack of unsolved crimes, it makes Nick question his own feelings of self-worth, especially after hearing about another, real suicide: that of one of his "old friends". Nick must search through his memories of their relationship of centuries past to determine why she killed herself, and why he shouldn't.