Spotlight On... John Mack, former chief executive, Morgan Stanley

Mack the Knife?

That's the man, and five'll getya ten old Macky's back in town. Two years after stepping down from the day-to-day runningof Morgan Stanley, and three months after retiring as its chairman, he has a new Wall Street role as an adviser to the private equity behemoth KKR, or Kohlberg Kravis Roberts.

What's he going to do for the barbarians?

The barbarians? Oh, yes, the "Barbarians at the Gate", as Kohlberg Kravis Roberts became known in the Eighties when they pioneered leveraged buyouts. Mack is going to join the ranks of corporate grandees – including the former Caterpillar boss James Owens and Bertelsmann's old co-chairman Richard Sarnoff – who give Kohlberg Kravis Roberts the benefit of their wisdom on potential investments.

Will he fit in?

No doubt. If there is one thing private equity owners are known for, it is cutting costs at the companies they acquire, and Mack became known as "the Knife" for his cost-slashing as head of bond trading at Morgan Stanley and again when he briefly ran Credit Suisse First Boston a decade ago, where he cut 10,000 jobs. Such teeth, dear.

I'd forgotten about his stint at CSFB

He was forced out of Morgan Stanley in 2001, after feeling that the chief executive Philip Purcell reneged on a deal to let him take the top job. But when the Purcell regime collapsed into infighting, Mack was brought back to a rapturous, trading floor reception.

And what a face

He was once memorably described as "physically resembling a crumpled, half-burned baked potato with a pair of overturned furry horseshoes for eyebrows". At 67, he does look beaten up, but then he did steer Morgan Stanley through the credit crisis.