When Toolbox and "Big Bird" tell Sam to leave Ravi to them, he says, "What, and let Ravi help out with the foundations of the M62?" The M62 motorway is a motorway in Northern England, connecting the cities of Liverpool and Hull via Manchester and Leeds. The road is 172 km long; for 11 km it shares its route with the M60 motorway around Manchester. The motorway, which was first proposed in the 1930s, was built between 1971 and 1976. Sam's comment refers to the criminal practice of hiding bodies under large structures during construction.
The character of Rocket is named after someone John Simm knew as a student, this is also why you hear Elton John's Rocket Man song throughout the episode.
Layla pulls down a Jimi Hendrix poster to reveal "NF" sprayed on the wall behind it. The National Front (NF) is a far right, white-only political party whose major political activities took place during the 1970s and 1980s. Its popularity peaked in the 1979 general election, when it received 0.6% of the overall vote. Although considerably less popular in 2006, the NF still fielded election candidates and Sam would have known of them.
When the lights flicker, Gene remarks sarcastically, "yeah, well, thank God for OPEC." The Organization of Petroleum Exporting Countries is an intergovernmental organization of developing countries founded in the early 60s and headquartered in Vienna. In 1973, during the Yom Kippur War, Arab members of OPEC implemented oil embargoes aimed at the developed world, initiating the 1973 oil crisis.
Sam questions a woman who identifies herself as Layla Dylan. She later admits that her name is Leslie Roy, saying she named herself after "the music." Her fake first name references the song "Layla" by Derek & The Dominos, and her fake last name references Bob Dylan.