Flashy investment bankers have been ordered to stop showing off or face an abrupt check on their highly-paid careers.
Colin Fan, head of the markets division at Deutsche Bank, warned he was fed up of their "boastful, indiscreet and vulgar" behaviour and it would not be tolerated.
The blunt personal video message from Mr Fan to all staff in the division, which was revealed by the Financial Times, warned employees that their emails, conversations and conduct would all be subject to scrutiny.
It reflects anxiety within the financial sector over corporate reputations as regulators rake over records and emails in the wake of scandals such as Libor rate-rigging.
Mr Fan said: "This is an important message. You need to pay close attention. It's about how you communicate in this company.
"You may not realise it but right now, because of regulatory scrutiny all your communications may be reviewed.
"This includes your emails, your conversations, and your conduct. All of this is open to scrutiny. Some of you are falling way short of our established standards.
"Let's be clear: our reputation is everything. Being boastful, indiscreet and vulgar is not OK. It will have serious consequences for your career and I have lost patience on this issue.
"Communications that run even a small risk of being seen as unprofessional stops right now. I need you to exercise good sense and sound judgment.
"Think carefully about what you say and how you say it. If not, it will have serious consequences for you personally."
Embarrassing internal communications between staff at financial companies have come to the fore in recent months as regulators publish details of investigations into the Libor rate-fixing scandal which have seen billions in fines handed out.
One probe last year revealed an exchange suggesting champagne was being sent by traders at UBS to brokers at City firm ICAP for helping them profit from manipulating the benchmark interest rate.
Deutsche Bank was fined 725 million euro (£591 million) as part of a 1.7 billion euro settlement over other rate-rigging allegations involving a raft of European banks last December.
Earlier this year, another senior Deutsche executive reportedly said that those without the necessary "moral compass" could not work for the bank.
The company employs more than 98,000 people including more than 8,500 in the UK. Its investment bank is the fifth largest in the world and the largest European-owned business of its kind.
A source close to Deutsche Bank confirmed Mr Fan's message was an internal video sent to all markets staff in April.
The bank said in a statement: "A new culture is taking hold, step by step, here at Deutsche Bank. The substance and tone of this video is intentionally direct and part of an ongoing programme.
"We expect every employee to understand and comply with our standards."