Parallel/Parallels **** Irish Cream *** Alan Lucien Xyen & X Factor Dance Company **** Rosie Kay Dance Company & Odd Johan Fritzoe **** All shows are at Dance Base until Saturday. Times vary.

There are times when Morag Deyes, Dance Base's artistic director, is like a personal shopper for Fringe-going dance fans. This year's choices are among the best she's ever hunter-gathered for her Grassmarket spaces.

Parallel/Parallels, the first new work from Plan B in six years, sees the audience having to choose which side of the (unseen) studio area to sit on. But in director/ choreographer Frank McConnell's whimsical exploration of parallel universes, there is no right or wrong, only different paths and perspectives of the performance, thanks to shifting screens that mediate what each side sees. Free-floating between sectors is musician Michael Marra, interpolating wry ditties and magic tricks. Four dancers sing and speak, while voiced-over text filters in scientific facts and Malcolm Shields is an on-stage link between audience and the physical/metaphysical concepts that send bodies skipping and whirling. If the first half feels a little fragmented, the second resolves into a heartfelt celebration of what it means to be alive, a particle-person journeying through time and space, relationships and experiences. The ending, with Shields a cosmic venturer has a joyful wonderment that is magical.

Irish Cream's triple bill sees gamesmanship surface in various guises: Beatbox Bingo weaves it into a motivational exercise, Match delves into Gaelic football and Hanging in There runs it round the block to the tune (or rather rhetoric) of the Good Friday Agreement. Nick Bryson and Damian Punch (aka Legitimate Bodies Dance Company) deploy the verbiage of political negotiations as if it was a movement primer or a choreographic tool. The sober-suited duo deliver snatches of verbatim text while physically striving for parity and balance. It's funny and perceptive on so many levels, not least in the suggestion that their contact improvisation techniques might help politicians get to grips with slippery opposing parties.

Match, choreographed and danced by Fearghus O' Conchuir with Matthew Morris, showcases combative strengths, but with more than macho athleticism. The rivalry is gladiatorial. If only Beatbox Bingo (performed by Catapult Dance, choreographed by Rebecca Walter with live music by Justin Carroll and Edward RosenBerg III) had delivered its ideas as succinctly as the other pieces, this would have been a full measure of crackingly good dance. Instead, this take on corporate teambuilding games sprawled, with too many sections dulling the original edge. A pity, because the three dancers have class and the two musicians are prepared to interact with the tongue-in-cheek action.

Edinburgh-based X-Factor Dance Company, Steinunn Ketilsdottir (Iceland) and Alan Lucien Xyen's company (from Norway) all use text in their performances, yet each work touches on matters not to be spoken about: death, terminal illness, the loneliness of waiting for the ideal life-partner. This last piece, Crazy in love with MR PERFECT, is a bitter-sweet duet - Ketilsdottir joined by Brian Gerke - in which the togetherness of a dance rehearsal becomes a dialogue of wishes and confessions. In time and it will snow - choreographed and danced by Xyen with Suzie Davies - is a delicate vignette: the words are diary entries written by a terminally-ill patient, the movement furthers the sense of heightened awareness.

In between, X-Factor revisits Unbroken (2000) with choreographer Alan Greig joined by the lithe Peter Kyle in a wistful piece that touches on the spirit world. Though Greig's comic-couthy medium jolts the reverie, her presence reinforces the underlying yen that there is "something there" unbroken, after death. Balls, choreographed by Odd Johan Frtizoe (Norway), is really a three-star bout of contemporary prowess and break-dancing fun where huge balls are both props and sound-systems. The energy never flags, and it's inventive. No such problems for Rosie Kay and Morgan Cloud in Double Points:K. Based on a work by Emio Greco/PC - the original was part of the Edinburgh Festival programme in 2001 - this exacting duet is an Everest of synchronicity, timing, defined body lines and stamina. All this, and an adherence to Greco's mantras of breathing and the dynamic relationship between forms. Double Points is not about emotional interactions, indeed in its own way it's as much about parallels (mirror images, echoes, amplifications) as McConnell's "other-worldly" construct. For Kay, this choreographic re-interpretation is a triumph. Catch it if you can.