“If I said goodbye to my first true love/My heart would break in two/For I’m halfway still in love with him/And half in love with you/Tra-le-la-le-la-le-la-triangle,” Patsy Cline sang, her voice dripping with sorrow. But then she’d strike a triangle (the instrument) with a pling so lighthearted that you knew that she was half laughing at herself, too. A love triangle involving a woman (Charlotte Akin as the original book slut), her publisher husband (real-life spouse Jim Jorgensen), and her husband’s book-agent best friend (Dan Via) is at the center of Harold Pinter’s 1978 play Betrayal. The Fountainhead Theatre’s production hits upon most of Pinter’s witty plings and reveals the triangle for what it is: a wretched, banal exercise conducted by people too self-absorbed to make fun of themselves. Pinter’s narrative is so seamless that director Sarah Denhardt’s decision to fill scene changes with projected stills of the actors in intimate poses feels intrusive—as do Akin’s and Via’s faux-British accents. But as soon as Jorgensen (pictured here with Akin) takes the stage, it becomes clear that the other two characters are just satellites orbiting drunkenly around him: With his wildly expressive eyes, Sherlock Holmes–esque brow, and deeply resonant voice, Jorgenson manages to swerve between the cattiness and the tragedy that are at the heart of Pinter’s play. The show starts at 8 p.m. Thursdays through Saturdays (with 2 p.m. Saturday matinees), to Saturday, Sept. 11, at the Theatre on the Run, 3700 Four Mile Run Drive, Arlington. $20. (703) 920-5923. (Bidisha Banerjee)