- "Well you don't tell the person being cheated on, you confront the person who's doing the cheating — didn't they teach you anything at Harvard?"
- ―Roz to Frasier
DYNAMIC DUEL – Frasier counsels a listener, Gretchen (voice of Glenne Headley), when she fears that her fencing instructor husband, Gunnar (guest star Brian Cousins), is having an affair with one of his students. Frasier concludes from the thrust of Gretchen's story that his sister-in-law, Maris, is the swordman's student/girlfriend. Both Martin and Roz advice Frasier to stay out of it, but he's determined to help Niles fight for his marriage.
- Kelsey Grammer as Frasier Crane
- Jane Leeves as Daphne Moon
- David Hyde Pierce as Niles Crane
- Peri Gilpin as Roz Doyle
- John Mahoney as Martin Crane
- Irene Olga Lopez as Marta
- Brian Cousins as Gunnar
- Glenne Headley as Gretchen
- First appearance of Marta, who is mentioned many times over the course of the series
- Marta speaks German.
- Frasier speaks Spanish
- Niles speaks French