Tamsin Greig, Iain Glen, and John Sessions head cast in Nina Raine's production of Chekhov-inspired play by William Boyd. Runs 28 Feb - 13 April inclusive. Booking via theatre website: www.hampsteadtheatre.com n Heather Neill to see on the night but may not write up till Friday for S aturday coz she can't really do two overnights in 72 hours and is already r eviewing the Gate for us on Thursday.