They break out of Fox River prison at the very end of season 1, starting in episode 21 and completing it in episode 22.

When the escape happens

  • The actual escape operation begins in season 1, episode 21, titled “Go” , when Michael and the team finally put the tunnel plan into action.
  • The escape continues and concludes in season 1, episode 22, “Flight” , where the Fox River Eight make it over the wall and go on the run.

In‑universe timing

  • A fan‑compiled timeline places Michael’s time in Fox River at roughly a month and a half, with the breakout occurring in late May 2005 within the story’s timeline.
  • So in terms of watching order: finish season 1 to see the prison break itself; season 2 then follows the aftermath of that escape.

TL;DR: If you’re just wondering “when do they break out of prison on Prison Break?” — it happens at the end of season 1, across episodes 21 and 22.

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