Babson's wit and whimsy (Line up for Murder, etc.) are given full play here, in a sharp-edged bat affectionate sketch of two senior-citizen ex-movie queens--Evangeline Sinclair and Trixie Dolan. They've come to London to attend a retrospective in Sinclair's honor, staged by her one-time costar, now entrepreneur, Beauregard Sylvester. The ladies are put up in a plush brownstone apartment. On the floors above live a half-dozen aspiring drama students and Sylvester's stockbroker grandson Jasper, who owns the house. Evangeline and Trixie have scarcely unpacked when the body of a young woman is discovered on the premises by Mick, a Mohawk-coifed upstairs dweller whose scalped, murdered body is next to be found--by Trixie's strait-laced, humorless daughter Martha. Here, unfortunately, the so-called plot--its murders, their motivation and resolution--is the flimsiest of structures on which to hang the author's portrait of two jaunty relics of a bygone golden movie age. All in all, then: fun but flawed.