Dubbing it "the world's first dedicated luxury hybrid vehicle," Lexus says its latest gas-electric entry will slot between the IS and ES, and is the first Lexus with a four-cylinder engine -- albeit one that works with the latest iteration of the Lexus Hybrid Drive System to crank out a total of 187 horsepower. That motivation gets shipped to the front wheels via a high-efficiency continuously variable automatic transmission. A good many of the HS 250h's technical details were not disclosed, nor was its projected fuel economy. But Lexus did confide that the five-passenger four-door does will boast a class-leading 10 standard air bags when it goes on sale in late summer--at an also undisclosed price. Other LS 250h highlights include a richly-appointed, well-isolated cabin, Vehicle Stability Control, and the availability of a new Hard Disc Drive Navigation system and Lexus Enform and Safety Connect telematics package.