The play is written by J.C. Bloem and focuses on the internal dialogues of two characters: a man and a woman. The play's core is the emotional exchanges within these characters, not physical appearances or dialogue between them.
While there are no "actors" in the conventional sense, the play is typically performed by two actors who take on the roles of both the man and the woman, delivering their respective monologues.
Therefore, to know which actors have played the roles, you'd need to look at specific productions of the play, as the cast would vary depending on the specific staging.