Set on the back porch of a home in Chicago, “Proof” — Madison Theatre Guild’s newest play — offers audiences a vehement two hours as they watch a story of girl who has to deal with the loss of her recently deceased and mathematically brilliant father.

“Proof,” a Pulitzer Prize-winning play written by David Auburn, is the story about a girl, Catherine (Jessica Jane Witham), who gave up her academic ambition to care for her mentally ill father, Robert (Stuart Brooks), who has revolutionized the field of math in his lifetime. As she sits depressed and alone on her 25th birthday, she drinks to forget the death of her father, while a young prot?g? of her father, Hal (Nathan Figueroa), frequents her home.

While a romantic relationship builds between Catherine and Hal, Catherine’s older sister Claire (Susan Finque) comes back to Chicago from New York for their father’s funeral. As Claire stays in Catherine’s home, she criticizes Catherine and offers her unfriendly advice to improve her life. Even as Catherine is unappreciative of the suggestions, she begins to ask herself how much she is actually like her father.

Directed by Joan Brooks, “Proof” has the audience on the edge of their seat through the entire play as they anticipate new plot twists. Witham’s performance as young, angry and irritated Catherine is excellent and at times comical as she regularly picks on Claire and Hal with her sharp sarcasm. While Finque takes on the role of a demanding older sibling, she uses her acting talent to try to take control over Catherine and Hal personal lives. As she does this, she gives a strong performance, accomplishing the role of the commanding sister.

Brooks and Figueroa’s acting throughout the play contribute to the overall success of the performance. Figueroa’s role as an uptight math nerd who hopes to be as brilliant as the late Robert is hilarious. While he tries to impress Catherine with his math skills, he is consistently nervous around her, waiting for a spark to happen between the two. As for Brooks’ role as the wise father, he uses both his voice and his body to convey the enormous struggle of a mentally ill person, as well as the pressure and responsibility put on those who care for him.

One of the best aspects of “Proof” is the theater it is presented in. With around a 100-seat capacity in the Evjue Theater, the audience is no more than five feet away from the actors, allowing them to become encapsulated in the emotion of each character and feeling as if they are part of the play itself.

Overall, “Proof” gives the audience a night full of undeniable entertainment. Each actor shares a convincing role while the plot line makes the audience anxious for more. But to completely understand the magic of the play, you will have to experience it for yourself.

“Proof” will be playing at the Bartell Theater from Feb. 5 through Feb. 21. Tickets are $15. For more information, please visit www.madstage.com/bartell/.