How does Behn use disguise to develop this play’s themes?

Characters have been in costume for nearly the entirety of the play; however, it is not until this scene that does disguise truly figure front and center. Yet, unlike the masquerade costumes or series of other disguises in the play, the disguise that Hellena assumes in this scene fails to trick her intended audience. Hellena disguises herself as a young man or boy in order to fool Angellica and Willmore; only Angellica is tricked into believing that Hellena is a messenger boy. Willmore, on the other hand, is ultimately able to see through her disguise and recognize her for who she is. The significance of this discovery and failed disguise is twofold: it indicates a perceptiveness in Willmore not attributed to any other character in the play (than perhaps Hellena), and it signifies also that the female attempt to inhabit the male world or take on the persona and corresponding actions of a male character is ultimately not possible. All other disguises up until and following this instance in the play maintain gender integrity; females, though disguised, remain female, and males only ever take on another male persona. The one and only time that the gender boundary is crossed is when Hellena dresses as a man; this is also the only time in the play that a disguise is transparent. This failed attempt at disguise can be extrapolated beyond Hellena’s personal inability to convincingly execute a male impersonation to women’s inability (and, potentially, impossibility) to embody a male-dominated world. This play has addressed the limitations of female characters on many levels, and here we see one more example of how a woman simply cannot successfully move beyond her domain as female into the power-yielding world of men.