In Sally Clark's Moo, Moo will not marry because it's expected, although her sister Sarah all but admits that she is not marrying for love. Moo takes pride in being able to shoot at and hit a tin can while it's in the air, though her sister declares that it is "useless."
Perhaps this is at the core of Moo's character: she rejects anything that seems ordinary. Certainly, Harry gets her childlike attention when he borrows her gun and, much like the Wild West attractions at a carnival enthralls children with his mastery of a gun, captures Moo's imagination...
...You just keep hitting it so it stays up there. (throws the can up, shoots, keeps the can up for a long time)
MOO stares, dumbfounded...[He] leaves. MOO stares after him. She throws the can up, tries to shoot it, misses. She stares back after HARRY.
Moo seems to want more of a challenge. Of Harry she says:
I knew the moment I laid eyes on Harry...that...I wanted him and nothing was going to stop me from getting him...he had a certain look in his eyes. A depth and a wildness...
We discover early on that Moo forgives all: this only seems to drive Harry away, but she loves the chase!
This brings us to Harry. The author, in her Preface, describes "rotters"—men who "seduced wealthy women and then deserted them." We can assume that Harry is a rotter. He comes to the MacDowell home ostensibly to bring news George's death—the MacDowells' only son—saying they were friends in the war. It is possible they may have fought in the same company, but it is also likely they never really knew each other. It may simply have been a ploy to gain the acceptance of the family.
When Harry suggests they run off, Moo offers: "Elope?" Harry says no. Moo then says marry, but his form of whatever lets the audience know that this isn't love. The play opens as Harry is having Moo committed to an insane asylum—where he keeps her for five years, and still she forgives him. He admits to being unfaithful; she excuses it. He marries twice more, and disappears for years, sending Moo postcards from obscure islands all over the world (somewhat obsessive in itself)—as if intent upon annoying her...but like the lighter at the end, she says:
I wouldn't let go.
Moo certainly is obsessed by Harry. And while he is a cad, it also seems he can't resist her when they are together—wearily admitting at one point that he loves her. Harry's postcards keep Moo annoyed enough to keep chasing him—perhaps a Freudian slip on Harry's part? Her devotion shows Harry that she is "more than he bargained for."
What seems to draw them is their incompatibility: the things that Maude rambles on about drive Harry crazy—he throws Maude down the stairs. Patsy excuses everything he does. He derisively dismisses her with:
Did anyone ever put a bullet through your brain, Patsy?
At the end, Harry finds Moo at the nursing home, having almost completely succumbed to senility; he is shaken. The Moo that chased him to the ends of the earth is almost gone. The Moo that believed she could make it work is fading. The only glimmer is:
Harry. Are you going to send me a postcard?
When Harry returns one night with a gun, he speaks to her tenderly. Moo knows him. As he put her hand under his on the gun (the thing that started it all), she does not resist. They pull the trigger together. In losing herself, Moo was taking away the fire that linked their lives. That which drove them apart, also joined them...a true paradox.