When Jess and JJ go to the spot where Jennifer (Jess's sister) disappeared there is a place called White Rabbit in the background. The White Rabbit is from Alice in Wonderland where a girl disappears down a hole. Jennifer disappeared.
Although released after Need for Speed (2014), it was shot before. Aaron Paul was so impressed by Imogen Poots on this film that he encouraged her to apply for the female lead there.
The suicide pact made between the characters is established for period New Year's Eve - St Valentine's Day. When Martin and Jess meet her father opposite the Houses of Parliament, the clock on the tower of Big Ben shows 4.40pm. At that time of year it would already be dark but it is bright and sunny.
JJ: You see... Jess needs to feel important... Maureen, she needs to feel... loved. And you, you just need to grow a brain. See... you can solve your problems. But me... I can't.
Martin: We belong together, we're a team I mean we're the worst team the world has ever know and if I were picking none of you would have made it to the subs bench but still.