Sort:  
  1. Bb5+ Nxc2
  2. Rxc2+ Bc5
  3. Rxc5+ Qc7
  4. Rxc7+ Kb8

How exactly do you checkmate now? :)

Rc8 check
Kc8
Ra1 to c1 checkmate

That right?

!Rc8+ with mate in 1 to follow.