The anti-corruption fighter Ma Wen is surprisingly forthcoming and approachable for a senior mainland official.
At this year's Chinese People's Political Consultative Conference in March, Ma, 64, spoke candidly with reporters about the central government's efforts in tightening spending and clamping down on official corruption.
But when prodded with questions about Wang Lijun, the former Chongqing police chief who sought refuge at the United States consulate in Chengdu in February after a fallout with his superior, Bo Xilai, Ma grew guarded and rushed away.
Ma has been seen as a strong contender for elevation to the party's Politburo, and some whisper there is even a slim chance she may become one of the very few women to serve on its standing committee, the party's supreme decision-making body.
A small and pleasant woman, Ma is deputy secretary of the party's Central Commission for Discipline Inspection. She is rarely seen in public and to the outside world is as mysterious as the organisation she oversees.
Apart from what is given in her official résumé, information about Ma is scarce. She was born in Wuqiao, Hebei province and worked in Bayan Nur in Inner Mongolia before being admitted to Nankai University in Tianjin, where she majored in history.
Ma served in a number of capacities at Nankai, including deputy party secretary, before being promoted to a central government role, largely as a reward for toeing the party line in dealing with the Tiananmen student movement in 1989.
After eight years at the National Population and Family Planning Commission, Ma moved to the intra-party disciplinary commission in 1997, and became its deputy secretary in 2004. She was the third woman to hold such position, after Deng Yingchao , wife of late premier Zhou Enlai, and Liu Liying.
A former classmate of Ma's from Nankai University told the Southern People's Weekly students used to refer to Ma as "Big Sister," as she was several years senior to them and so capable.
The classmate said that despite Ma's current prominence, she easily mingled with everyone at class reunions and similar occasions. "However, she doesn't forget her status at the same time," the former classmate said.
The commission, an intra-party apparatus that tackles official corruption, has been criticised for operating above the law and for the dubious tactics commission officials have used, including extra-judicial detention and illegal wiretapping.
Ma herself experienced first-hand some of these practices when a highly secure landline she used to brief President Hu Jintao over a disciplinary investigation in Chongqing turned out to be monitored on orders from Bo Xilai, the municipality's disgraced former party secretary, according to a New York Times exposé in April.
Ma, who has also served as Minister of Supervision since April 2007, has been credited for bold initiatives in tackling official corruption, including a push for greater disclosure of government spending on vehicles, overseas trips and entertainment.
She has headed a crackdown on corrupt officials who send family members overseas and stash funds they pilfer from the state in foreign accounts.
Still, Steve Tsang, a specialist on Chinese politics, said Ma's low public profile might undercut her chances for promotion to the Politburo Standing Committee. "I really can't see how," Tsang said. "There could be a surprise [for Ma Wen], but the surprises are unlikely to be so dramatic."