England had been given a warning, as ominous as a low growl from the undergrowth in the Sundarbans. Their victory in the first Test, in Chittagong, came via the slim margin of 22 runs, Ben Stokes required to dredge them out of trouble on the fifth morning and preserve England's record of winning each of the nine Tests they had played against Bangladesh. But that run was about to come emphatically to an end.
In Dhaka, over the course of three frenetic days, Bangladesh claimed their most significant victory since being granted Test status in the year 2000; in 94 previous Tests they had only ever beaten West Indies and Zimbabwe.
The hero of the hour was 19-year-old offspinner Mehidy Hasan, playing only his second Test. As England fretted and twitched, Mehidy dazzled and bewitched. The teenager collected a slew of records and accolades - including the best match figures by a Bangladeshi - as England lost ten wickets in a session of mesmeric spin bowling, tumbling into the Mirpur cracks as the stands suddenly came to life.
There was a famous hundred for Tamim Iqbal, too, providing Bangladesh's foundation - although they twice threatened to squander their advantage, first slipping from 171 for 1 to 220 all out, then allowing England to recover from 144 for 8 to post 244. But on a dusty, turning surface, Mehidy and Shakib Al Hasan were more than a match for England, even after the openers had assembled a 100-run stand to seemingly give them a foothold in the chase.
Cricket's youngest Test nation (at the time) had beaten the oldest, and the significance was clear. "It's not easy for me to say, but it's a good win for Bangladesh cricket," conceded England's captain, Alastair Cook. "Maybe some things are bigger than one game." His counterpart, Mushfiqur Rahim, put it more succinctly: "Now it's party time."
Alan Gardner is an associate editor at ESPNcricinfo. @alanroderick