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2. Mark's "Arm & Hammer" Shirt
During the climactic "I'm coming back for everything" confrontation between Mark and Eduardo, keep an eye on Mark's shirt: it bears the logo of baking soda company Arm & Hammer.
As odd as Mark wearing such a shirt might seem, this is actually a ridiculously specific Easter egg relating to co-star Armie Hammer.
You see, it's often stated that the company Arm & Hammer was named after legendary business magnate Armand Hammer, even though he wasn't actually born until 30 years after the company's formation.
And in case you hadn't figured it out, Armand Hammer also happens to be Armie Hammer's great-grandfather.
Given that it's tough to imagine why Mark would wear such a shirt otherwise, there's no way this wasn't an intetional nod to Arm & Hammer's mythic origin story.