There’s the Spirit of Christmas, and there are spirits at Christmas; not those that slide out of a bottle on Christmas Day and then whack you over the head the next morning, but shape-shifting spectres who lurk in dusty old rooms, or dark tunnels, or wild woods, or in the Christmas television ­schedules. Clearly, M.R. James is the go-to guy for ghosts. On Christmas Day on BBC2, the versatile Mark Gatiss adapts one of his tales, called The Tractate Middoth. That’s the name of a book of Talmudic commentary that lives in a dusty college library, where it is guarded by a malevolent spirit in priestly garb. The film also represents Gatiss’ directorial debut, for which he’s adopted an expressionist style, somewhere between Fritz Lang and the House of Hammer. The acti