Jacqueline Carlin was strolling around LA one day when she noticed a house for sale and went in. “I was from back East, amazed that I could walk in wearing jeans and a T-shirt to just look around,” she says. She was definitely taken seriously anyway. The next day, her Realtor called to tell Carlin the house was hers.

That “rush” experience led Carlin into an elegantly pursued obsession for years to come. “Just that little LA house was all it took,” she says. “When I went back to Martha’s Vineyard I started a house based on octagons.” That house would eventually inspire the one here. Now two houses sit on opposite coasts, similarly conceptualized, successful in purpose and resolutely gratifying.

The Carmel Valley house is a tribute to old Spanish/Mediterranean styles and seems positioned at the top of the world on a high plateau with only expanses of land, sky and ocean around it, sheltered by heavy evergreens along the garden walls—“Hilltop House.”

The front of the house faces east into a vast origami landscape of folded hills—hundreds of acres on the Quintana Ranch. The back looks west into every sunset of the year, the distant ocean a lovely smudge, whitewater like a single thread lying beside it. These visual luxuries are all on view inside the house, too. Carlin explains that she based her idea on two octagons, each bowing out of the main footprint with two sets of ultra-quality, oversized French doors bracketing windows of the same dimensions that render half the shape pure light while creating a straight line of glass. One octagon holds the dining room; the second the master suite. East light gentles mornings into the master and sunsets grace the dining room.

A set of huge French doors with three narrow insets of clear beveled glass open into the house. One steps into a state of wonderment upon entry. The scope of the interior is felt like good weather, with delight and not a lot of thought because the details are balanced and refined to the effect of three-dimensional poetry. Ceilings here are very high, pyramided in the octagons, vaulted in the others (living room, kitchen, foyer, hallway and two of the three bedrooms) with massive beams of bleached Douglas fir. The heavy plaster walls with beautiful corners and archways are so thickly bull-nosed they suggest a new interior possibility. The beams’ edges are also smoothed. “First they are ‘add-softened’ to lose those sharp edges,” Carlin explains, “then they’re sanded and finally sealed.” All the walls are white, all the beams, wood frames and kitchen cabinets are bleached fir and the floors big squares of terracotta. The roof is Spanish tile and the exterior stucco is the color of browned butter. Dark evergreens are the best accessories around the property.

The master suite is a huge octagon. It opens onto the east lawns, has a fireplace and a very private bath. The second and third bedrooms open onto the west lawns and they share a Jack-and-Jill with double sinks, a large shower and a separate Jacuzzi tub with a wall of windows facing west.

The main rooms are actually one “great room”—the living room, kitchen and octagonal dining room open to each other in a generous space fully windowed with the French doors and framed windows seen throughout the house. A handsome fireplace at one end is a subtle but perfect visual counterweight to the wonderful ethereal qualities. Hilltop House is a presence.

PRICE: $2,295,000. 25525 Terra Grande, Carmel Valley. Contact Glen Alder, Sotheby’s International Realty, 601-5313.