I first saw Lydia Panas' work from the Mark of Abel series when it was exhibited at Foley Gallery, New York, in early 2010. Back then, I remember thinking that the photographs � muted group portraits, in which obscurely connected individuals stand before anonymous rural backdrops � were engaging but hard to access. Each photograph is simultaneously a tempting puzzle, its subtle visual clues inviting you to 'work it out,' and a rebuke, resisting your attempts to draw any conclusion about its subject. Whether that discomforting effect is an intentional experiment with formal tension or, rather, a weakness in Panas' project, remains unresolved in this book.

'Group portrait' is an awkward description of what Panas does. The phrase suggests a formality, a sense of occasion, which these images are conspicuously lacking. A sense of 'inbetween-ness' is generated by the almost listless attitude in which the photographer captures her subjects. These figures rarely engage directly, physically, with the viewer or, in any dynamic way, with the frame of the photographs, though we are subjected in nearly every image to their blank yet unrelenting gazes. They 'do' almost nothing and the result is an air of expectancy, a sense of pause. George Slade puts it neatly, in his short text towards the end of the book, when he refers to the way in which these loose compositions of figures and ground create a 'dwelling within the photographic frame,' a space in which we think about and around the people depicted.

This delicate sense of presence is offset by occasional moments of explicit drama or theatricality, as in an image in which a young woman wears a white wedding dress � its slightly odd fit and her almost mournful expression informing us that she is only playing at the role of bride, and that half-heartedly. The visual reference to the commercial photography of 'occasion' underlines Panas ambivalent relationship with physical appearance � it gives us, she seems to say, everything and nothing; clues to human behaviour and character without any real or accurate understanding.

There is action of a subtle, gestural kind in Panas' photographs. At her best, she has a technical mastery and sense of visual space that activates the reader's imagination and invites interrogation of her images. In The Mark of Abel where family groups are depicted (without captions or explanatory text) this is particularly acute � what can we glean about these people and their relationships? How are they similar and how different? We wonder about the character of the woman who adjusts her partner's hair in the background of one photograph, while the 'daughter' figures in the foreground address the camera both more frankly and yet, because of their more plain and androgynous appearance, more anonymously. A slight sharpening of focus brings one woman into relief while her male companion drops back into the image, raising a protective, or self-conscious, hand to his chest. Is he unsure of the camera or disdainful of it? In this respect, in these telling gestures, The Mark of Abel has something in common with the cryptic communications of Thomas Struth's Family series, though it is less varied in scope.

When I last saw Panas work in an exhibition, it was the piece Kitty, Christine and Kira, selected for Foto8 Summershow at the Host Gallery, London. The sense of transience this later portrait evokes is heightened by the way in which the photographer has caught her beautiful subjects at odds posturally with themselves and each other. It seems more resolved than some of the work in The Mark of Abel � I look forward to seeing further Panas books in print, which are slightly less opaque, slightly less of a puzzle, than this one. —Faye Robson