SAN FRANCISCO, Dec. 29 — In brand-new offices with a still-empty game room and enough space to triple their staff of nearly 30, a trio of entrepreneurs is leading an Internet start-up with an improbable mission: to out- Google Google.

Steve Newcomb, Lorenzo Thione and Barney Pell are the founders of Powerset, a search engine.

The three started Powerset, a company whose aim is to deliver better answers than any other search engine — including Google — by letting users type questions in plain English. And they have made believers of Silicon Valley investors whose fortunes turn on identifying the next big thing.

“There’s definitely a segment of the market that thinks we are crazy,” said Charles Moldow, a partner at Foundation Capital, a venture capital firm that is Powerset’s principal financial backer. “In 2000, some people thought Google was crazy.”