[rú dǎo tāng huǒ]   

如    蹈    汤    火    蹈：踩；汤：滚水。如同在滚水、烈火中行走一样。比喻处境艰险。

in deep water and fire

如胶如漆    如锥画沙    如埙如箎    如臂使指    如痴似醉