Menaechmus II of Syracuse
Menaechmus of Syracuse is one of the twins and main characters of the story. As a child, he was separated from his missing brother, and dedicates several years to searching for him. At the beginning of the play, he enters Epidamnus with his slave Messenio, unaware that his long lost brother is also there. He is often impatient with Messenio but eventually grants him his freedom. His presence in Epidamnus causes a lot of trouble due to his being mistaken for his brother, though he does not figure this out on his own. He decides to embrace Erotium's offering of food, drink, and sexual favors even though he assumes she must be crazy.
Menaechmus I of Epidamnus
Menaechmus of Epidamnus is the second twin. When he was a child, his father, Moschus, took him on a business trip. While traveling, Menaechmus I is kidnapped and adopted by a businessman in Epidamnus. When his adopted father dies, Menaechmus I gains all of his assets and becomes a wealthy man. Menaechmus I is disrespectful to his wife, frequently and unabashedly visiting the prostitute that lives next to them (named Erotium), and berating his wife for being a shrew. He is frustrated by the confusing series of events initiated by his twin's visit, but upon learning his identity, decides he will return to Syracuse with Menaechmus II.
Erotium
Erotium is the prostitute that lives next to Menaechmus of Epidamus. Erotium mistakes Menaechmus of Syracuse for Menaechmus of Epidamnus several times, and grows frustrated with her conversations with the men who do not understand what she is talking about. She is clever, alluring, and industrious about getting what she wants from her patrons.
Wife
Menaechmus I's wife is described by Menaechmus and her own father as shrewish, though the reader may have sympathy for her situation. She is upset that Menaechmus I so blatantly visits Erotium, and relies on her father for support later in the play when she deems her husband to be mad because he does not recognize her (when in fact she is speaking to her husband’s twin).
Messenio
Messenio is Menaechmus of Syracuse’s slave. He enters Epidamnus with Menaechmus of Syracuse, and quickly mistakes Menaechmus of Epidamnus for his master. He is a good slave in that he behaves and does what his master asks of him, but he desires to be free. He asks his master for freedom, which is accidentally granted by Menaechmus I first but then confirmed by Menaechmus II when Messenio is able to prove the two are brothers.
Peniculus/Brush (Parasite)
Peniculus is a “parasite” stock character. Though Menaechmus of Epidamnus confides in Peniculus, all Peniculus cares about is getting what he wants: food. To achieve his goal, Peniculus leeches onto the wealthier Menaechmus of Epidamnus and tells him what he wants to hear so that he will be rewarded.
Doctor
The doctor is hired by Menaechmus’ wife and her father to cure Menaechmus of his madness.
Father
Wife's father and Menaechmus I's father-in-law. Initially, when Menaechmus’ wife tells her father about her troubles with Menaechmus, her father takes Menaechmus’ side, believing that he visits Erotium because he is unhappy with the marriage. However, upon realizing Menaechmus’ “madness,” he sides with his daughter and seeks help from the doctor.
Cylindrus
Erotium's cook.
