They came dressed in black, faces covered, armed with a kitchen knife.
But it was what was left uncovered that drew attention to the CCTV footage.
As two robbers fled an Adelaide hotel with Monday night’s takings, one stumbled down the stairs, briefly exposing his backside to the cameras.
Pankaj Kaushik from the Hilton Hotel in the Adelaide suburb of Hilton said the pair “came in, pointed the knife and then they left”.
Police said the robbers stormed the South Road venue’s gaming room just before 11pm on Monday and held staff and customers at knifepoint while they raided the tills.
“The female staff member pressed the alarm when they came in and pointed a knife towards her, and yeah police, (it) was pretty quickly they come over,” Mr Kaushik said.
The bandits remain on the run after fleeing down nearby Mallen Street before detectives could flood the area.
Hotel staff believed the attack was premeditated, saying the security shift was due to start about 11.30pm, just half an hour after the hit took place.
“We have got good protocols over here in the Hilton but we will still have to review it and see what best we can do for our staff protection,” Mr Kaushik said.
” … It is a stressful situation, if you look at it we are just coming to do our work and facing that kind of a scenario is pretty stressful for us.”
Shaken employees were left unharmed but given the day off on Tuesday and offered support.
Police appealed for anyone who recognised anything about the crooks to contact Crime Stoppers on 1800 333 000.
They said the man carrying the knife was wearing a black, hooded jumper, beige trousers, beige working gloves and grey shoes with a white base.
The other man had fair-coloured hands and was wearing a black, hooded jumper, grey tracksuit pants, white runners and a black Nike backpack, police said.