Correct!The Ides of March
Clue 1: George Clooney starred in The Ides Of March (2011) and Hail, Caesar! (2016)
(Julius Caesar was murdered on The Ides Of March in 44BC)
Clue 2: Steel Prophet opened their 2000 Messiah album with a song called The Ides Of March. Myles Kennedy just released a new song with the same title.
Clue 3: Steel Prophet covered Gangland and The Ides Of March/Purgatory medley.
Clue 4: Referring to the Samson song Thunderburst from their Head On album which was co-written by Thunderstick (who was shortly drumming for Maiden before Clive joined the band) but not recorded by Maiden yet. Steve got all writing credits for The Ides Of March on Killers though. Although not completely the same, both songs are much alike.
Your turn, @Diesel 11 !