With impish profundity, Alfred Hitchcock jammed his 1951 thriller Strangers on a Train full of twins and pairs, including two men who act out each other’s murderous impulses, two identical-looking women with glasses, and even the sight of Hitch himself lugging a double bass. Now there’s one more duplex to add to the list: the new DVD release of Strangers, which teams, on one CD-size platter, both the original U.S. version (still available on VHS) and a British cut rediscovered in 1995 (and just issued on tape a few months ago). The new cut inserts about 90 seconds, lengthening the first encounter between stolid, unhappily married tennis pro Guy (Farley Granger) and indolent, fey playboy Bruno (Robert Walker) with a few sharp additional lines (”Now, didn’t you ever feel,” purrs Bruno, ”like you wanted to kill somebody, say, one of those useless fellows that [your wife’s been] playing around with?”). There’s no amplification of Bruno’s homoerotic come-ons, as some reviewers have argued; the innuendo was always there. But Strangers‘ longer cut does, oddly, delete the Stateside version’s tag ending, which ties the action up just as it began — another bit of doppelganger ingenuity. The best of all possible Strangers would use the British setup and the U.S. wrap-up. But of course the master of suspense might never have authorized one ”master” version of his tennis-court suspenser. From beyond the grave, he’s still playing doubles.