A helmeted policeman drags a woman down a barricaded street, one arm tightly locked around her neck. Dozens of riot police in full gear look on as the young woman, wearing a short black dress, gasps for air.
The scene is captured in a dramatic snapshot taken at a sanctioned opposition rally in Moscow in May 2012 that erupted in violent clashes with police and led to hundreds of arrests.
The woman in the now-famous picture, 19-year-old Aleksandra Dukhanina, made it home unscathed that day.
Three weeks later, however, she was detained for allegedly hurling rocks at officers during the protest.
She has since been under house arrest pending trial, unable to receive visitors, denied access to the Internet, and unable to use the telephone or even write letters.
She faces up to 13 years in prison if found guilty.
Dukhanina is one of 22 protesters charged with participating in "mass unrest" and assaulting police at the May 6 demonstration on Moscow's Bolotnaya Square.
The so-called Bolotnaya case has come to symbolize the brutal tactics employed by the Kremlin to quash protests as President Vladimir Putin faces the biggest show of opposition to his 13-year rule.
It comes amid a broader crackdown on dissent that has included repressive new laws and a string of raids against civil groups across the country.
"This trial could become the culmination of the attack against civil society and nongovernmental organizations that began with Bolotnaya Square," political analyst Nikolai Petrov says. "The May 6, 2012 protest is a very serious turning point, an apex in relations between authorities and the active part of society. How these relations will evolve, I think, will depend largely on the stance authorities will adopt on this matter."
Of the 22 people charged in the case, 15 remain in pretrial detention and four are under house arrest.
One defendant has been battling prosecutors' attempts to intern him in a psychiatric hospital. Another protester is on an international search warrant.
The first demonstrator to be tried, Maksim Luzyanin, was sentenced to 4 1/2 years in prison after cooperating with investigators and pleading guilty. Many see the stiff sentence as a sign that heavy jail terms await the rest.
Investigators say their probe is nearing completion, suggesting the next trials could take place in coming weeks.
The Bolotnaya affair is likely to further grow in scope.
Investigators are still tracking down some 70 other protesters they suspect of disruptive behavior on May 6.
In December, they merged the case with an ongoing inquiry into opposition leader Sergei Udaltsov, whom they accuse of scheming along with two associates to overthrow the Russian government.
The authorities claim the plot was financed by Georgian politician Givi Targamadze and involved provoking riots on Bolotnaya Square.
The investigation spread beyond Moscow for the first time earlier this month, when several civil activists connected to Udaltsov were raided and questioned in the central Russian city of Orel and in Novosibirsk, Siberia.
With the "Bolotnaya" case gathering pace, supporters, too, are stepping up their efforts to free the defendants.