` ` Ice Age : Continental Drift '' is the fourth installment in the series . Reviewer said the formula is getting stale . Like the equally stretched-to-the-breaking-point `` Shrek '' series , `` Ice Age '' has accumulated too many characters with too little to do , and all-star vocal stylings ( `` Continental Drift '' adds Jennifer Lopez , Drake , Nick Frost and even Joy Behar , to name a few ) can only do so much by way of compensation . Ray Romano , John Leguizamo and Denis Leary play the main characters .
` ` Ice Age : Continental Drift '' is the fourth installment in the series . Reviewer said the formula is getting stale . Ray Romano , John Leguizamo and Denis Leary play the main characters .