Penrhyn Cook’s series of photographs, Holiday Reflections, are absorbing enough in their own right. Colorful and festive, the images are just askew enough to warrant a closer look. Are we looking at double exposures? What do we make of the giant fruit and a rainbow on a city block? In the context of Kehler Liddell Gallery’s annual holiday show — titled“Deck the Walls” and running at the Westville space through Dec. 24 — the title of Cook’s series earns itself a double twist, as the works of fellow gallery members on the opposite walls are reflected in the photos’ glassy surfaces. Images layer on images, an apt depiction of the show as a whole, in which all the gallery members play a part.