What’s more, Mr. Mahathir is doing this by campaigning for the political party that was set up to fight injustices allegedly perpetrated while he was in power. But never mind that. Facing a Trumpian Mr. Najib — another ex-protégé of his — who promises to “Make Malaysia Great,” Mr. Mahathir has pledged to save the country from this scandal-ridden government.

Over nearly a decade in office, Mr. Najib and his administration have been plagued by wild allegations, ranging from various counts of financial impropriety to conspiracy to commit murder. Among all the kaffeeklatsch and the hearsay, all the tales of lavish living and cronyism, one story line stands out: a case of kleptocracy so immense that it is has spawned criminal and regulatory investigations in at least 10 jurisdictions around the world.

The scandal in question has to do with the sovereign wealth fund 1Malaysia Development Berhad, or 1MDB, which Mr. Najib set up in 2009 to spur economic development in Malaysia. According to the United States Department of Justice, money from the fund has been used to purchase ritzy apartments in Manhattan, mansions in Los Angeles, paintings by Monet and Van Gogh, a corporate jet, a luxury yacht — and even to finance the making of “The Wolf of Wall Street.” Some $681 million may also have wound their way into our prime minister’s personal bank accounts.

Yet 1MDB will play little to no part in Wednesday’s election.

Why? For one thing, from the outset Mr. Najib used his power and influence to interfere with investigations into the scandal. He replaced the attorney general who was getting ready to file criminal charges against him and sacked cabinet members who were openly criticizing the government’s handling of the allegations. Four members of the parliamentary accounts committee charged with investigating the case were promoted to cabinet positions, and the committee’s work was suspended.