Neil Simon's darkly humorous play The Odd Couple debuted on Broadway at the Plymouth Theatre in March, 1965. It is the story of two opposites, Felix and Oscar, who, for some reason, have become best friends. Act I of the play is set in Oscar's large (eight-room) and very disorderly apartment (it is described as slovenly in the stage directions). Oscar is hosting a poker game with Murray, Vinnie, Roy and Speed. Felix is absent and we later learn he is distraught after splitting with his wife and has even contemplated suicide.
Depending on where you are, there is probably very little chance of seeing the production live on stage, but you might check your local live theatre listings. It is a favorite and often staged. Another option is to go to Youtube and search. By far the best version of Act I on Youtube is the one starring Nathan Lane as Oscar and Matthew Broderick as Felix. Brad Garrett, Ray Romano's brother on Everybody Loves Raymond, is quite funny as Murray the Cop.
Another good option is the 1968 movie with Walter Matthau and Jack Lemmon. It should be available on movie sites. Since it is a movie, the dialogue is not always exact and things are left out, but much of the banter between the poker players in Act I is left intact. There's the funny exchange where Oscar is handing out sandwiches and remarks that the green sandwiches are either "very new cheese or very old meat."
One suggestion would be to watch both the Youtube video with Nathan Lane and the movie as well. Have a copy of the original text of the play and follow along. Also read the excellent summaries and critical essays on this site.