Baby Dee, Bush Hall, London

Baby Dee, to put it mildly, is a massively hard sell. A 54-year-old male-to-female transsexual built like a rugby-union prop-forward (she's a former tree surgeon) and sporting a wild frizz of carrot curls, she plays perilously close to being disregarded as a Coney Island freak-show turn, which, indeed, she once was. That she named herself after a friend's neighbour's "retarded child" and has been championed, and produced, by Will Oldham (who has a perverse sense of humour at the best of times), also prompts a raising of the eyebrows.

Then, of course, there's the voice, and the stage manner, a kind of hellish amalgam of Jake Thackray, Kevin Coyne and Monty Python's nude organist. Anyone who counts Harry Ruby – who wrote "Hooray for Captain Spaulding" for Groucho Marx – and medieval Gregorian plainchant as inspirations, is a pretty rum live prospect.

Brought up in Cleveland, Ohio, the "mistake by the lake" immortalised as a Midwest dead zone in the film American Splendor, Baby Dee is a creation that the sex-obsessed Robert Crumb, a Cleveland homeboy, could have dreamt up on a very bad day.

But as fans and collaborators such as Marc Almond – standing next to me – would no doubt attest, there's a rare and genuine artist lurking behind all the Tod Browning shtick. Breezing boozily between piano and harp, she makes an unsettling, but rather wonderful, whoopee out of songs from her latest album, Safe Inside the Day, and the earlier The Robin's Tiny Throat. In between the cackling and the asides ("I like squeezy bits!", and something about fellating herself), songs such as "Big Titty Bee Girl (from Dino Town)", which extols the virtue of keeping an albino around the house, astonish: "You can poop on his pie/ You can piss in his sink/ And even if you spit in his eye/ He'll still be in the pink".

But the neo-Tin Pan Alley routines, for all their all genuinely unnerving entertainment value, aren't perhaps the real draw here. The intricate baroque folk of songs such as "Small Wonder" ("I hid my aces in a widow's lap") and "Black but Comely" – both played on the harp – have a mystery and sense of terror that call to mind Emily Dickinson. Her talented band, which includes the Scottish drummer Alex Neilson, and Devon Sproule's husband, Paul Curreri, on guitar, fleshes out the detailed melodies. Freak or unique? Unique.

Baby Dee appears with Current 93 at the Queen Elizabeth Hall, London SE1 (0871 663 2500) on 21 April

Interesting? Click here to explore further