crack open
[for something brittle] to break or split open. The egg cracked open and a chick worked its way out. The side of the mountain cracked open and molten lava flowed out.
crack something(wide) open
1. Lit. to crack or split something. An incredible eruption cracked the volcano wide open.
2. Fig. to expose and reveal some great wrongdoing. The police cracked the drug ring wide open. The newspaper story cracked the trouble at city hall wide open.